Clythio

Reliable, steady, easy to setup, change batteries and calibrate, rigid, long lasting batteries, etc. - compatible with a lot of computer heads (I use Cycleops Joules because I have Powertaps).
Will keep them both - I have a 170 and a 167,5mm. Bought in order to use with any wheelset, including disc wheels.
Seems to be a bit "low measuring" at peak numbers - easy to understand if principles of "tension path" strain-gauges position is analyzed, due more contribution form "inner" parts of the "beam" - gauges are on external faces.. but it doesn't matter if you want to compare sessions/races.
On peak efforts like standing starts or rolling sprints, it can show up to 5% numbers below Powertaps on 5s-15s efforts. But it's precise, it doesn't floats, you can compare different efforts on a very, very coherent way.
On any effort above 50% of max, ie, >1min, it goes on pair with best Powertaps I have - which I consider the gold standard, sorry for all other solutions with gauges in different places than on a round, perfect, big diameter torque tube... ;-).
Considering all those factors and the price, I would recommend InfoCrank for track racers.
It is ISIS compatible, allowing adjust for all frames - I'm using 108mm/68mm without any problem on my Fuji Track Elite.