They are all made by caspers electronics and distributed by different vendors.
I purchased one for 15 dollars at a swap meet and had to swap two wires around to get it to work on the 87 TPS sensor. I guess its useful for setting the idle voltage since it uses lights to show when its in spec.
Problem is it brings on full fuel enrichment at "3/4" throttle. Now think back about the tps sensor and how 3/4 throttle voltage is dependent on how its adjusted.
Mine would hit 2.xx volts on the TPS and then spike to 4.86 at closer to half throttle. It caused a rich condition at part throttle sometimes.
Mine crapped out on me and started showing 4.86 at all RPMs, so I took it off, set the TPS to 4.5 WOT and .42 idle and it runs faster and has a better fuel curve than with it attatched.
If you can get your TPS sensor to read above 4.2-4.5 at WOT then dont buy a TPS-TEC. Even if you can't, dont buy one. Just get a new TPS.....