There really is no best car for SQ, especially compared to SPL. What you need to do is figure out what you want to put in and find a car that can hold it. Generally you don't want a really wide car, or a car with a huge center console. The more symetrical the better.

 

dwvw is right, get the lowest console, many different types of vehicle s win championships every year, it will all come down to proper application of the gear you get,,i bought my neon to do a sq car with, i liked the dash and very low console, wasnt to hot on the doors but made some radical changes to correct what i didnt like about them, its been said many times here,install,install,install, get great gear, apply it in the optimum way and you will win the finals, i promise, just kidding

 

While at first glanc the Mclaren would seem to be the obvious choice, it presents other difficulties to a pure SQ install, like price.

 

Maybach would probably be a decent vehicle. The Top Gear guy got the test one up to 250km/h and he said it still had zero road noise.

 

I judged an old camaro at SBN a few years back. It was great. The dash curved away from the driver as it extended downwards and there wasn't much in the way of a center console.