They are very solid guns. Nice and light and reliable. The ergonomics are (as already stated) love or hate.
I got used to my Benelli M4s90's feel and ergonomics therefore I love the feel of the MR1 (on my short list of stuff to buy). It definitely has a shotgun feel to it, if you're not used to using a longer stock, I'd suggest the tele stock since you can adjust it quite a bit to fit your length.
A nice Aimpoint or other red dot would be a good combination, but It has some nice LPA ghost ring sights which are very nice irons.