funkpilz
Well-known
Owning an M2 myself, I would recommend keeping that one. I was torn up between M2 and M4 in the beginning, but after a bit of use, I find I don't mind the "slow" loading and rewinding at all. Not sure if the M4 has other advantages, but I like the M2 mostly for its simplicity so I doubt any of those would sway me.