So after reading some posts on here suggesting to turn POP off, I did. Then I read some suggesting to turn it on, so I did. Here's my experiences:
POP off: Obviously less J outs. I only got one J out with POP off. K and Ka alerts seem to be fine, no extra distance.
POP on: POP on seems to make some of my Ka alerts ramp up really quick, which I don't really like. I'd rather have a gradual ramp up than a crap your pants ramp up. Ka and K alerts seem to be the same distance as POP off. I've also had many more J outs, maybe around 6.
Conclusion: I'll keep POP off. For anyone still deciding or hung up about it, you really have to do your own 'tests' and see what suits you best.