I like the Speed Passions. I've run SP and Tekin, I like the feel of the SP better. Both are good equipment, and have timing, turbo, etc. functions if that's allowed at your track. I have a brand new Tekin R1 Pro, never even had anything soldered to it. It's a sensorless speedo, and if you're running 17.5 you may be better off with a sensored system, but if you're interested shoot me a PM.