That setup is fine, similar to mine. I use a DCM150. I've heard the 200L is a bit harsher in the highs but I haven't heard one. You can probably compensate for that with eq and it has more headroom which is good.
You might want to go with a mesa 4x12 if you haven't already bought the cab. The vertical and horizontal 2x12 rectos are not available stereo/mono (and mesa won't let you special order them that way anymore...custom shop my ass). But all mesa 4x12's are pre-wired stereo/mono.
If you really want that particular cab and want to run stereo, you should order the cab with 8 ohm speakers rather than 16. (Mesa will do that... and sell you the stereo/mono plate, but won't wire it up stereo/mono from the factory... did I mention what losers they have become??). It comes stock with 16's, and if you convert it to stereo/mono it's 16ohms per side in stereo, which is quite a load for that amp. If you get it with two 8's, you can convert it and it will be 8 ohms per side stereo and 4 ohms in mono (I have a 2x12 horizontal recto that was made for me that way... before they became such losers....). The axe is very cool in stereo, you'd miss out on some fun if you ran it mono only. But lots of folks here go mono and it's still an amazing unit.
I do still love mesa stuff, I use all mesa cabs.... but jeez, "custom shop" and they won't even wire a 2x12 cab stereo/mono, despite the fact that all of their rack units and rack power amps are stereo.