Both are good packs but I'd take the dye any day. I Love the way the dye packs fit on me. As far as the zero g pack you really don't have to worry abouts pods falling out but I tried one on and would take the bunker kings one over the hk. I never liked hk because of how over priced there stuff is for what you get.
You told him to get the BK pack over the HK pack because HK overprices their stuff, when the Zero-G pack is cheaper than the BK pack.
Which is the smoothest? DM, probably, but Axes shoot really nicely.
Which is the lightest? I'd put it between the Ego and the Axe, the Ego might be slightly lighter.
Which shoots the fastest? It doesn't matter.
Which has the best board? I'd give this to the Ego.The Redline board has a ton of features, but I find that the interface leaves a bit to be desired. DM doesn't even have an OLED. Not really a big deal, but I think it should be there.
Which has the highest resale value? None, DM's and pre-LV1 Egos are plummeting in resale value right now, and Axes won't be too far behind. Paintball guns in general depreciate quickly. Buying new is for suckers.
Which has the best stock barrel? Probably the DM, but by the tiniest of margins. They all have really nice barrels and you won't notice a difference between them.
Which has the best features? Define features, this isn't something you can just put a number on and declare one gun better than the other.
Which is the most efficient? Probably the Ego, but I wouldn't at all be surprised if you can get the Axe to be more efficient.
Overall which is the best gun? Up to you. None of these guns would be something I would pick, much less buy new, but it's up to you.
Axe pro: 699
Don't buy any of these guns new. DM's drop in resale really really quick right now. You can get a used DM14 for much less than 799, and you should be able to snag an ego11 for half of what it would cost new. And I personally would never pay 700 for an Axe when the old model goes for around 250 used, and is identical internally.
My responses in red. In short, what everyone above said. None of these guns are definitively better than the others, and I highly recommend you get some hands-on experience with these to help you decide which one you prefer.