Just for another perspective, I've been with Site5 now for over a year and have had a total of 3 accounts hosted with them.
My initial experience was a bit mixed - support response time was great, but they kept saying they'd fixed my problem and hadn't. It lasted off and on for several months, apparent load and time-out issues. About 3 or 4 months after I started seeing the problems they disappeared almost entirely and things have been great on that account since.
When the $5 deal came out it was too good to pass up so I went ahead and bought another account. I've done little with it aside from hosting a Tech Preview mirror (ideal for the purpose) so I can't say much for its overall stability or anything, but it seems good from what I've seen anyway.
My real problems with them came when I decided to try them for a business-level host, using one of the existing packages (because they don't have business-specific packages). This was when it became clear that there really is a lot of "luck of the draw", with them as well as really any *budget* hosting company (Dreamhost, Bluehost, 1and1, etc. - they're all pretty similar).
First off I spent quite a while researching *other* hosts before coming back to them. Ultimately other hosts were either *way* too stringent or expensive for their services ($40/mo for 1GB storage and 50GB bandwidth or something), or they seemed shoddy, or just as much of a "crap shoot" as Site5. I figured I'd had good experience with Site5 and with the money back guarantee (60 day) and the low, low price I wasn't worried.
However there was still the question *which* package to choose, and here's where the problems began. I wanted the package that would give me the highest guaranteed level of site resources. According to their web pages that would be the "Diamond" package, with 32 clients per server (that's a number they quote in their advertising).
http://www.site5.com/hosting/diamond.php Unfortunately in trying to confirm this I just couldn't get a clear answer. Eventually someone told me that the "resource allocation" was proportional to the space and bandwidth allotments and that the "$5 deal" plan would inherently have higher resource allowances and fewer clients per server/resource availability. That seemed too good to be true but he insisted that was the case.
Then I found some info on their forums saying the 32 client limit was probably not in effect any longer since some hardware changes to their server, though they claimed the overall level of resources per-client was still the same or better given the hardware upgrades. In other words they claimed to increase server power by say 10 times while only increasing client load by 8 times or something. Still, it seemed dubious, especially since they still advertised the 32 client number (and do to this day). Other issues like Site5 not being part of the Better Business Bureau and inconsistencies/lack of clarity in their advertising/promises continued to fuel my skepticism. But given the lack of risk involved and my past relatively good expeirence I figured I'd give it a try.
Unfortunately I ran into problems right away. The issue was *extremely* high server load at certain times of the day, sometimes consistently for several hours. I began charting the load and saw very disturbing trends. Often times I couldn't even access my control panel. After several discussions with support they finally determined it was one errant user who was playing with Ruby and did some stupid things. OK, fine, they figured it out, problem solved. Only it wasn't - it continued, off and on, for the next 2 weeks. This was in the middle of the 60 day evaluation period and had begun almost as soon as I got the account, so it was not encouraging, and unfortunately I had little time to fully evaluate before I decided whether to get a refund or not.
This problem prompted me to once again try to get a clear, firm, solid answer on what their "best" (in terms of resources) package was. I eventually took the step of even emailing one of their high-level managers and posting a lengthy message to the forums. I never got a response to the email and they determined that my public post was "inappropriate and inflammatory" so they moved to a private "customer inquiry" or something, to which I never got a satisfactory response either. Some my questions included the resource issues and possibility of false advertising (32 clients per server), as well as asking why they weren't BBB members. I can see why they felt threatened, but it was pretty low of them to just bury it.
After that bad experience with the forums and management, and the continuing resource problems (which did eventually seem to stop, but I wasn't going to count on it staying that way), I decided to cancel. I haven't regretted the decision, although I maintain (and even renewed) my other two accounts and continue to have good performance from both. I've definitely made good use of the accounts and appreciate their services. It's just unfortunate that they can't find a way to maintain consistency across their server fleet - it's really luck of the draw.
If I could have had guaranteed resource availability - for example in a Virtual Private Server (VPS) setup where there are actual resource divisions - then it would have been ok and I'd have stuck with it. But the shared environment just wasn't acceptable for business use. Frankly I don't think what I experienced was acceptable for any purpose, but it's cheap and you have to accept compromises. If you think about it logically there's no way they can offer what they're offering at that price without signficantly overselling, even though they claim they're not. There certainly are no free rides.
So my advice is yes, give them a shot. You have little to lose with the 60 day money back guarantee and whatnot. But I would strongly advise setting up site monitoring systems as soon as you get your account and finding out the name of your server so you can search the forums for issues associated with it. From what I've seen certain servers just have a history of issues and it tends to *continue*. You do have the right to ask to be moved to a new server if you experience issues and I would recommend trying to find this out by doing stress testing, 24 hour monitoring, and forum searches within the first few weeks of purchasing your account, rather than waiting until you actually do have a problem long after you've setup your website and have all kinds of things configured. The process of moving to a new server can be painful and it's best done before you've spent much time configuring.
I suppose this kind of caution and testing is advisable no matter where you get hosting. It just seems all the more advisable with Site5 given the inconsistencies. That being said if you do get a good server the service is unbeatable at the price, so that's good. Other seemingly comparable hosts with which I don't have personal experience are
http://www.dreamhost.com/ http://www.bluehost.com/ http://www.1and1.com/ etc. I've heard lots of people saying good things about Dreamhost and they have similarly "insane" resource allotments for the money...
- Oshyan