Gt5

I loved GT3 and liked GT4, but I have a few questions when you have time:

How many of the 200 premium cars are musclecars?
How much more difficult is it to "hop into one of your cars and race"? GT4 took longer than GT3, more menus, intros, etc. and I've heard that GT5 is even worse. Is it really that bad?

My biggest disapointments from GT4 were 1) no '77 Trans Am 2)no Porsche (Ruff doesn't count) 3) no Ferrari 4) I couldn't get a rebel flag for the roof of my '68 Charger. Holding off on buying GT5 untill these are remedied.
Truthfully, GT4 was slightly beyond my gaming abilitys and I'm pretty sure GT5 will make me feel even older.