I just turned on my evo since I bought my nexus, I can't even describe it. Even after I put GB on the evo. It still blows the doors off.
I'm just waiting for my Trident case to arrive before I activate mine. The GB update for my Evo feels kind of sluggish and my battery life still blows even though it's improved somewhat.
I have the same experience with my EVO after GB.
That is mostly why I decided to keep the NS4G as I know my signal issues will be addressed soon enough. When that gets fixed, the NS4G will certainly be the best Android phone I've owned to date.
I've gotta say, I think the Epic I had for a month started up just as fast with Froyo.
Maybe it's a Samsung thing???