The newer models are very accurate, but the trap speeds are not. Idon't know about the old model, they aren't temp. compensated and they only have two axis not three. So I wouldn't thinkthey are as good but both the new and old version will give you an idea of how much you gained from a mod.
I bought my Gtech Comp at a local speed shop, since I'm in Canada it Cost me ~$400. It would have been around ~$250 US.