I agree with TCL. Diecast.org's "Lists & Reviews" is a great place to start.

The review included there of the Gurney/Foyt/Grant #3 MkII car is a little long-winded (the author tends to be that way)but gives some information you might find useful.

http://www.diecast.org/diecast98/html/asp/list_reviews/xq/ASP/id.GMP1201307/qx/reviewpix.htm

I have four GMP GT40's: two MkII's and two MkI's. And I like them all. The two LeMans winners (#2 MkII and the #6 MkI)won three LeMans races overall and the #3 MkII was the '66 pole-sitter and played a huge role in giving Ford the ultimate '66 LeMans victory. I also have a silver MkI street car with wire wheels and have added appropriate black FORD racing stripes to the rocker panels that really make it come alive.

If you're interested in price, eBay is a good place to start. If my memory serves me correctly, they were originally priced in the $400-500 range, but, if eBay is any measure, are now in the $800-1200 range. These are impressive models even though they don't have the detail found in the 1:10 Exotos.