I don't care about fretboard radius, neck length, tremolo or hard-tail bridge. The only thing i am concerned about are pickups - 24 has PRS manifactured ones, M. Holcomb has Seymour Duncan. Which are more suitable for a larger variety of genres, and overally which sound better?
Well, you are basicly asking "which pickup is better, the factory generic one that is put into cheapest guitars, or the brand name one that loads of professional guitarists use?". The answer seems pretty obvious, dont you think?
Joža je kul. On ma sirove z dodatki pa hambije.
are some real pickups and a cheaper guitar outta the question ?  watch some videos on the SD picksup cuz signature pickups can vary. some people like ice pick some like a hot mess 
"Sounds better" is a subjective term. The bigger question for me is not the pickups (generally SD's are better than generic factory pickups) but your question on multiple genres will be more impacted by the fact that the Holcomb ships from the factory in Drop C tuning. Obviously, you can change to standard tuning but why buy a signature guitar that you plan on changing (paying more for that signature model) just to turn it into a regular version?

You may consider buying a regular custom 24 SE (there are a lot of them for sale used at half the price and adding the SD pickups). 
the holcomb is like the best value guitar you can buy right now. it shouldn't even be a question
Prs se Holcomb is the answer
Quote by AcousticMirror
the holcomb is like the best value guitar you can buy right now. it shouldn't even be a question

Yeah I've heard crazy good things about it
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I have the Holcomb, its the tits. That being said, I bought it specifically for the scale length, the fretboard radius, the pickups, etc. The Custom 24 is a classic, and honestly if I didn't give a shit about any of the features of the guitar other than pickups, I'd probably get a mint used C24 (lots on Reverb) and buy myself the exact pickup set I wanted

Either will be good quality. Honestly I would try to think about the other features and take those things into consideration, at the minimum think about whether you want a fixed bridge or not. They are going to play pretty differently.
I'm just a kickin' and a gougin' in the mud and the blood and the beer.