Frankly there is little difference between the 2.

ST quote .1 of a horsepower difference. Probably a couple of hundred rpm, with identical props.

What sort of model do you intend for the motor?

If it's a scale or semi scale with a cowl, probably the ringed version. If it's something that is going to tear up the sky, the ABC.

Also consider what Dar Zeelon has said about life span.