Norwood says 1/32" accuracy with the LM2000. I'd say if YOU do your part, it will do that good or better.
As for tension in the logs, it's a fact of life, and the logs can and will move more than 1/32"...
My saw will saw 24" "wide" boards, and side to side it's spot on! If it wasn't, i'd ajust it untill is was and end the problem right there.
The band on a bandmill is like the chain on a CSM, if it's sharp and set right it does a great job. If it's dull it doesn't...
As for maintance? My LM has 2 grease zerks, and you put a few drops of oil on the track wipers daily. Put water in the water jug, and gas in the gas tank, other than that all that's left are oil changes.
Band sharpening is like chain saw sharpening. It get dull, you sharpen it. I replace bands as needed and sharpen them when i have a few dull ones. It takes me about 3 or 4 mins to change a band.
I have a CSgrinder to sharpen my chains and a band saw sharpener to sharpen my bands... If you don't want to sharpen them yourself, pay someone else to do it just like with CSchain.
Swing mills are great mills in there place, but most of us never get those huge logs all the time to need one, and band mills can "easily" saw wider lumber.... and look at the cost of those swingers compared to a bandmill... A LM2000 starts out at 5K, and it will handle 32" logs and saw 24" wide!
I don't care what anyone else buys, but it does bug me when i read that "band mills" saw wavy lumber when it's the "operator" sawing the wavy lumber. It's called "operator error"...
Have fun with whatever you choose ...
Rob