22% - 780,981 Credits
96' Skyine GTR - 698hp, nitrous
01' Cadilac Cien Concept - 989hp
04' Toyota X-Runner - 478 N/A tune
02' Subaru Impreza WRC Concept - 391hp, rally whore
03' Subaru Impreza Touring Car - 561hp Stg 2 Turbo
85' Metro Turbo 5 Rally Car - 455hp, rally, tarmac whore
02' Toyota Rally-something WRC concept - 501hp - pwnt
04' Nissan Fairlady LM Concept - 593hp
04' Honda Takata-Dome NSX - 493hp
99' Spoon Honda EK Hatch
02' BMW M3 CSL - 412hp
02' BMW M3 GT-R - V8, prize from M3 cup. - 554hp
American races are giving a good deal of trouble. I've yet to drive a musclecar that doesn't plow through corners like a boxtruck with no steering. Not to mention the fact that my 900hp Cien can't keep up with American LM type cars.
As for difficulty, GT4 SEEMS easier, but once you get to some of the serious races (20-something laps) pit strategy and tire choice are critical. I've yet to unlock endurance races, but I clearly have more to do.
I found it quite hilarious when racing the AWD Cup in the Begginer Races to find my 400hp Skyline (at the time) lined up in the grid next to a 4x4 Dodge Ram 1500.