Since I own both of them...
In short definitely 710 Axis.
710 has axis lock, I guess U've heard about that many times already
Much more convenient, easier, better & stronger than the liner lock.
If rust resistance is not a primary concern of yours, then go for 710 in M2.
Personally I prefer 710 blade geometry over EC.
To me EC chisel grind is definitely inferior to standart edge grind, even though you'll have to resharpen your 710 to get a decent edge.
I prefer normal thumbstuds on 710 over disk opener on EC, that eventually gets loose.
BM has torx screws not flatheads as EC does.
710 has a longer blade, that might be a plus or minus depending on your needs, donno
I've posted some more on my website about both knives. you can check there too.
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