Don't have this unit, nor the original it is based on. So easy to ignore me.
Apart from gain, the attack and release times (crest factors?) look slightly different on all three.
So somewhat difficult to compare, I'd think. Cos what works on bass on one might not work on vocals. And while the other is good on one vocalist, it might be less good on another or even on drums. Whereas the third is good on drums, but only when played fast. Otherwise the first might be better ? Don't think there's a fixed timing setting that works on everything. I'd be interested in program material, but then again, the original it's based on isn't cherished for that, AFAIK.
Anyway, either the stock unit is a magic one-trick pony, and it does that trick fantastically, or it works well on many differently enough materials to be satisfying -- no matter it's cheap as a unit. Trying Kenetec cells sounds legitimate to get closer to the original. I do believe a lot of testing and experience went into those replacement cells.
For now, however, personally, I'd be more interested in S/N, sweep, THD and IMD measurements.
Sorry,
The Party Pooper
