I checked the facts and of what I can find it would seem that Tekin is the better option at a glance. More professional looking and put together, and requires a little less assembly and work to function, plus the esc is a little more sophisticated for specific racing, rare for a small brush system, and cool at the same time. I'm sorry, but these just are simply not that popular and I've never got the chance to use one, but the mamba is a very popular and trusted motor, and it goes for twenty bucks cheaper, 130 vs. 150 on tower hobbies. At my local track, I know of a few people with mamba's, but never really got the chance to test or ask them about it being a 1/10 t4 participant.
~all I can say for now until I get my hands on these