PGMII NH3 is pretty good, but is the choice of the radical racer. Has a wire inside that can be snipped to retard the ignition.
PGMII spliced is also good, but more retarded than F3 PGMII. Has the same wire inside as the F3 ECU, but does nothing when snipped in either standard or spliced format.
PGMIII spliced is probably the choice of champions, in my humble opinion. Couldn't find anything inside to snip so didn't.
PGMIV is a pain in the ring 'cos of the expence of the card, but I've had 75hp out of a heavily modded 28 with an 010 card, on avgas and an extra half degree of advance. Didn't even open box with the intention of cutting any wires 'cos Paul would shoot me if I mess up a PiGMyIV
What would I use? F3 PGMII. Why? Because I have a few
What would I recommend? PGMIII spliced. Why? Because they work well and are reliable(ish).