By Toutatis, I hate to be the first naysayer, but SSMS has to be the biggest pile of steaming crap ever to be the excuse for a dev env. Using it is like trying to stride through molasses. I am constantly aware of the productivity it is costing me. Are two tools such an imposition, given that they work much better, and about three times faster ?
I don't use the RedGate tools, but this must be about the spot for a plug for them ;-)
On the positive side, I'd like to cite the improvements in the optimiser. Problem queries (that shouldn't be) in SQL2000 run sweetly in SQL2005. It's like oxygen - you only notice it when it's not there.
Now if only I could get SQL2005 to run with the old tools ....