We picked up a 2100MBH this year, I wanted a simple and hopefully solid built camper. I've had it out 4 times and leaving today for the 5th trip, I typically pull it 3-4 hours to various state parks. So far I have had no problems other than the normal cheap build quality issues. Those being the bath/kitchen caulking is garbage and anything held down with adhesives needs to be redone, the cap lights were one I had to upgrade the double sided tape.
I picked this unit because I wanted all aluminum framing and I didn't really want a slide. I wanted to stay as small as possible while still having a full size bed and wide bunks for my 12 y.o. twins. Something just big enough to hide out in bad weather but small enough to get them outside on these trips. I also use the camper half the time solo on trout fishing trips, but still have room for a fishing buddy if needed.
The wife loves the size of the bathroom and at 6'2" I've got no issues with headroom in the shower. However, a Dometic 320 will not fit without major modifications so plan your commode upgrade accordingly.
Since we do a lot of state parks and got our camper late this year we knew we would be doing a lot of dry camping. It has a nice 60 gallon fresh tank but the grey is only 30 so I use a couple aux tanks to make room for showers when the kids go along.
The kitchen is a bit tight on counter space if you use the stove a lot but I cook outside so we generally use the cooktop as a counter. I love the fridge! I know the 12 volt idea has a lot of doubters but I've been using a 12 volt dometic 50qt. for years overlanding and they work great. It gets cool fast, has tons of space and I never really boondock so I have no issues with running a 12 volt fridge off the battery for short periods. The only problem is there is no off switch to the fridge so you have to use the main power switch or wire in your own switch. I haven't found this to be a problem but when you park for storage if you forget to cut power the fridge will drain your battery.
The mattress is garbage, 4 trips and it is done. I'm trying out a new set up this week, I've got a 6" foam mattress topped with a 4" topper. The original mattress was two pieces to help the muphy bed fold up easy. I'm hoping the 6" and 4" will fold a bit easier than a solid 10" mattress.
Overall I'm pretty happy with the camper, it lacks a few things, pass thru lighting, porch light, dimmers on the interior lighting. The AC is loud but that muffles my snoring so everyone else can sleep but is kinda intrusive on hot rainy evenings when everyone is hiding out playing cards at the dinette. The camper pulls really easy and has fit well in every parks so far.
If you have specific questions let me know.