I've re-joined iRacing just for the MX5's - really like driving them. I tried the solstice back when I tried iracing a couple of years back and found it impossible to complete a race but the MX5's are sweet.
I got down to 144's on laguna seca with the MX5 roadster but goodness knows how people can do 141's on there!
Definitely the best driving sim out there