I thinking of getting a 320 AXG legion but I'm concern on how to keep the slide clean, we all know that comps accumulate carbon and lead. how would you maintain or clean the slide long term?, is there a reason to be concern long term?

First, I admit I do not favor comps, but have several guns with them. When they get crappy, I remove the barrel and/or comp, and soak the comp end in Eezox for a day or two, then work on it with a toothbrush if needed. Same technique with suppressors, I plug the ends, fill with Eezox or carbon cutter, and let them soak.

The P320 AXG Legion does not use a traditional comp. The ports are integral to the end of the slide and the barrel is simply shorter than normal. Disassembly and cleaning is the same as any other P320. IMO easier than comps that are installed onto a barrel and nothing to be concerned about.