I can't really comment on the 1G-FE, although I think my old GX81 had one. Good enough for daily duties I guess.
What I will say about the X90 chassis, is it handles superbly. I love how nimble and stable mine feels, even back when it was on stock suspension it felt so much nicer than my Z20 and A70.
Mine is 2JZ-GE but is still reasonably economical (for a big car with a 3l motor) so I can only imagine the 1G-FE would be even better again, although no doubt you'll find yourself using more throttle...
The only other comment I'd make is Chasers are hideous... get a Mark 2
Rumple dee pumple dee doo...