I shot an M2 and Versamax Tactical side-by-side to help narrow down that choice for myself. I ended up going with the M2. The Versamax was noticeably softer shooting, but also noticeably heavier - I was able to swing and hit targets with the M2 faster because it was lighter.
I don't feel like the additional felt recoil on the M2 is a significant hindrance. I've done a couple FLSC tactical shotgun matches (shotgun only) with my M2 and did not feel beat up at all by the end of the day - and I'm 5'4".
As far as reliability goes, you still see a lot more of the serious 3-gun guys using Benelli's versus any other models/brands - the consensus seems to be that the Benelli inertia guns are still the most reliable option. Personally, mine runs like a champ with little maintenance. It had about 1000 rounds through it before the last time I cleaned it (got used by myself and 2 other people) and had zero issues.
On the downside, it definitely does cost more to get an M2 decked out for competition. It's probably at least $150-300 more than what the Versamax Competition costs out of the box to get an extended mag tube, beveled loading port, better fiber sight, welded lifter, and a better bolt release and charging handle for the M2. On the flip side, you get to pick things out and get EXACTLY what you want when you customize an M2 like that - bigger mag tube if you want it (a lot of people are going with the 12 round tubes for 3-gun), more aggressive loading port modification if you want it, specific style of bolt release and charging handle, etc.
If you do go the M2 route, I've found that these guys do good work and have some of the best pricing for the typical mods (I sent my own gun and several shop guns to them):
http://www.hawkeyeordnance.com/