I'm not clear on all the intended uses of the 2 you are considering, but they are different and previous posters pointed out some qualities of each. I have a 2305 and a 4720...a 2720 would nicely fill the void for tasks too big for the 2305 and too small for the 4720. The 2305 is a fantastic mowing animal and I think removing the MMM is pretty painless and quick. The 200cx loader is slow and limited to light duty. Same with rear implements...
My take on the limitatons of the 2305 are speed, ground clearance, and light duty loader/rear implement capabilities. It can't go everywhere as it has limited ground clearance and limited, slow loader capacity. However, the strengths are mowing ability, ease of use, easy on the turf, ability to run small chores around the house area, etc. I use the 2305 for a lot of little stuff...I mow, clear snow from those tight places near the house, relocate implements for my 4720, haul firewood and rocks across the grass without trashing my yard, and all kinds of other things. I think you can probably do all of these same things with the 2720 and then some...but there would be a little more ground compaction if your on any type of wet soil. Also the loader would be quicker, but still limited capacity for the money.
I have sat on a 2720 and test drove one...very nice stance and comfortable. My 2305 on the other hand never ceases to amaze me at it's capability and is very comfortable as well. I wish I could take it out in the woods, but the ground clearence is low enough that I avoid getting myself in trouble.
If you don't need the turning radius of the 2305 or have sensitive, wet ground, then get the 2720 and enjoy the greater capabilities. Both are sweet machines...I give them both thumbs up...no matter which you pick, you will be happy! Enjoy and post some pics.