The matchup all depends on the model(GTI/Jetta)due to weight differences, the tranny(auto/stick), and of course the driver. The only 1.8t's that came in 150hp trim were the early models...00',01'. The 02'-03's came with 180hp/174ft.lbs..
All 1.8t's can be easily upgraded to the 200hp+ with simple mods such as a chip, exhaust, and a CAI. So, if you run into one at the track with even a hint of mods, be ready to get beat...
My wife and I recently purchased an 03' Jetta wagon Auto/tip. Although it's not the fastest thing on wheels it did manage to pull off solid 15.6-15.7 sec. runs. With the mods in my sig it was able to beat my SVT that was running solid 14.8's....with her driving it!

Like I said they can be made to run hard...imagine what simple mods would do to a 5 spd. GTI!!