Lots to think about then, Jack!
You really must have them running scared. Remember though, you could keep Floraworks going and it(and all your plants) would still belong to you, or, you could model for GW and be working for them, who would, in turn, own all your models!
Tricky but, it's a really great oppertunity for a job.
If you didn't already have Floraworks I'd say it was a no brainer, as it stands though, it's a hard decision: Keep what's yours and build an empire or, fold to the Bigman, for more money in the short-term. Good luck, whatever you do!