There are a few threads @ Midnite on these trailers & the Classic-250's (not the normal ones you buy retail) and it would be prudent to look on THEIR Forums for more info... there is a wealth of it there.
DC Solar Trailers MPPT-250
midniteftp.com
I have a Classic 200 & 150. They are great and do exactly as they are supposed to BUT these are Retail Models and not even the SL edition. Their fans ARE loud & annoying but as others have said they have a kit for that. The replacements are not any quieter - damned shame they didn't use fans with ball bearings as opposed to the cheapo's with sleeve bearing that make noise.
FYI: The US Army is about to start dumping similar trailers so keep an eye out. Additionally, the
US Forces have to replace all of their LFP Battery Packs (They are made by CATL) - DUKE Energy is already swapping them out, they started in December. There will be some damned good deals there folks.