I'm not really qualified to tell you what it's like to actually work with Vue as I've only had limited experience with it. I judge it primarily on its output; on the work that I see people create with it. Most of the images I see from Vue don't really impress me much, but it's really a subjective thing, so if the quality and realism of the output is important to you, the best thing you can do is check out some renders. E-On has some of the better examples on their website and you can find many more on the Renderosity Vue galleries and forums.
Pirates of the Caribbean is one of the very few examples of photorealistic work done with Vue and also one of the few film uses I'm aware of, but if you look at the actual use of Vue it was more limited than you might imagine. Vue was used to create 2D matte backgrounds for some scenes and there was notable post processing performed on the Vue output to make it look as good as it did. It's still important that ILM chose Vue over other products to do those elements, but on the other hand nothing else out there really could have even come close at the time as TG2 wasn't yet available and Digital Domain has control of Engen (their derivative of the "TGD" rendering engine that forms the basis of Terragen 2). For photorealistic purposes no other system even comes close - Bryce, World Builder, etc.
If you want to compare film work, Engen is a reasonably close cousin of TG2 and it was used extensively in Stealth as well as The Flags of Our Fathers, in both cases creating pretty seamless photoreal terrain. TG2 has also been used in commercials and other professional productions, even at this early stage. I think the bottom line though is that it's not as important what a big film studio can do with a product as it is what average artists can do. You also never know how much post processing was performed on something you see in a movie or commercial. So I would pay a lot more attention to the galleries of average users.
DeviantArt and
Renderosity are both good sources of large, active galleries of people using Vue. You've obviously seen what TG2 can do from the image posts here.
If Vue interests you enough to give it a try, they do offer a demo as well as a "Personal Learning Edition" (PLE) with watermarked output and a Vue logo on the renders. Both give you a good chance to get to know the Vue UI and workflow and see if you like it. There is no doubt that the Vue UI is more intuitive to some people because it's a lot more traditional than TG2. Only you can really say whether you prefer it, of course.
I don't think it's appropriate for me to comment on Vue's stability and similar details, but I think if you look at the forum posts on Renderosity and other public Vue forums over the last few months since the release of Vue 6 you should get a good idea of people's experiences with it, both positive and negative.
I hope that is of some help.
- Oshyan