The Sloter tires are almost exactly the same width but the sidewall height is about 1mm lower on the Sloter tires as opposed to the Scalex tires. The Sloter tires do crown a bit on the Scalex wheels but since the compound Sloter uses sands down every easily this should be easy to fix.
I've done some testing on this car with the new tires and it's much stickier on my new plastic Carrera test track than it was with the stock tires. It's lost none of the driveability that it had with the stock tires.
The best part is if you're familiar with Sloter tires you know they stick like crazy on wood and plastic tracks! So if you're looking to keep the stock wheels on your Scalex TransAm Jaguar this might be a good choice for replacement tires if you're in the market for them.