Ya got good taste
I prefer the MKV's but I bought the Ultralite.
Personally I don't think that there is enough of a diff between the rmag and the bee to sway me either way......I'm not a big fan of the 7bee for this reason.
Personally I feel like the 257 is the flagship of the bee line-up....but that is just me.....the 300 is nice but I have a wmag and went that way.
The bolt throw is nice for sure. Check out the brownings as well....60'...and they are nice as well.
Of the choices that you put out I'd prefer the accumark but it is gonna cost you more in the ammo end of things and you may want to get into handloading....but cost is negligible when you're having fun. Confidence in your equipment is everything IMO.....have a good look at them and get the one YOU like
tm