these are a must have for the tt-01 there so much better than the cva, yeah racing ones and are as good as the trf shocks but cheaper there as adjustable as the trf shocks and come with everything you need for easy set up and you can order a 3 racing rebuild kit with 2 other sets of pistons this rebuild kit does two shocks so you would need to buy two rebuild kits.
I got one set of this oil damper. They are very good on road. Much lower price than TRF make it easy to buy. For drifters you have to add more damper oil and change the coil spring to harder. But for onroad users you have to do nothing at all.