I think it's pretty clear, it doesn't make a whole lot of difference which level 2 count you use.
Using the brainspace you would be using for an ace sidecount for something else, like a sidecount for a sidebet, or a couple of key card sequences, is going to be worth more than the difference between HO2+A and Zen/RPC/Halves, etc. That's why I quit using it; I used the mighty HO2+A for a couple of years and it worked just great, nothing at all wrong with it, just that once I started getting into other things it was more effective to use single parameter counts plus these other things.