I thought I'd start a similar thread for GT engines, since the market now looks really competitive. With Maxima announcing their GT engine, the current selection is:
-OS Speed 21XZ-GT
-Reds R5T GT and R5R GT
-Picco EMX-GT
-Novarossi Mito GT, replacing the Ison GT
-different Nova based engines, such as Ielasi and Tesla
-one-off engines from respected tuners
...and reportedly more coming from respected manufacturers.
What's popular at your track? What are your experiences with them?