I assume you mean the Ford GT costing $300k. What car from GM sells for $190k? Is it a rare special edition of the Corvette? The base car is $60k, and even the Z06 starts around $90k.
The Corvette ZR1 has the same times around a track (e.g. VIR) as the (new) Ford GT. The C7 Z06 is as fast as the older (2005) one.
However, these don't tell the whole story. The GT is pretty highly strung whereas the Corvette's have a lot of room to improve with relatively inexpensive upgrades.
Is there a version of the ZR1 that's $190k (...currently available)? I thought it started at around $125k.
Overall the Corvette is the halo car... with a range from $60k up to about $125k. But I haven't actually walked into a dealer and asked them how much they'd want to order me up a ZR1 :)
However, these don't tell the whole story. The GT is pretty highly strung whereas the Corvette's have a lot of room to improve with relatively inexpensive upgrades.