Need some input

first off, im comming from the 240 scene. Always did 17, 18, and some 19" stretching. Might sound crazy but, im actually looking into some 20x10.5 F + R. -5 in the front and -15 in the rear. As far as fitment on a G50 Q45, what am i looking at. Im probably going to do some fender modifications and possibly custom fender flares. Do you guys think its a little bit too big? i was thinking 19's would look perfect on the G50 but a friend would let them go almost for nothing. What tire sizes would you recommend? Not used to 20s at all. Be honest tell me if the sizes are retarded for the Q. If its too much of a damn hassle for me, im going to wait for some Eurolines (ones that i really wanted to get) to pop up somewhere. I wasnt really planning to get those offsets and its alittle on the extreme side for me . I was looking for wheels with at most fitment of -7 for rears and not -15s lol. I need to get some shoes because my cars in the body shop right now and a car hit my fender/wheel/door. 

thanks guys much appreciated

seriously i dont want my car to look like..

[IMG]http://www.ipixelspot.com/files/11/sema%20cars%20043.jpg[/IMG]

are you talking about those chrome jline wheels for sale on vadriven? My boy was thinkin about test fitting those wheels on a gs400 because he has lowenhart 20's on it now and he is gonna give those to his brother's ls430. I was gonna drive up with him there to test fit them take some pics. maybe ill test fit them on my car to see how it sits...
 
But i know for the g50 you will need to run 235/35 tire all the way around and major hammering on the front inner well and fender pull so you have turning clearence. check out [B][U]tbreak[/U][/B], he fitted 20x10.5 +17 with fender roll and camber on the rear. so a little more fender pulling and camber will make that bitch flush. i dont think you will need fender flares for fitment.

[B]*edit- those wheels you are talking about is 20x9.5 -30 / 20x9.5 -40. Which means you can run a 225/35 or 215/40[/B]

20's can look sick if you put the work in.
 
[IMG]http://www.garage-freedom.com/img/gf_11_a01.jpg[/IMG]
 
but unless you are slammed and do the fender mods or tuck a higher offset rim i would go smaller. ridin 20's with gap or even stock 1/4 tsuraichi leaves the car way too high. personally, i like 18s on the g50.

19s ftmfw..
 
 
but im biased.
 
and have fun fitting anything less than 10+5 fronts and 11.5+5 rears. Shit have fun even with that lol.