I've been running my 4048MSD for about a year now without any problems with it. I'm in a similar situation to you, where we bought a farm with no grid connection, so just need to run a fridge while we're not there and then provide power through the weekend when we are there.
My only gripe with it, is the inability to equalise the batteries, and after inquiries with MPP Solar, it's not possible to add a separate controller further down the track, as the unit can not support voltages over 60V (caps rated to 63V)
Also since I'm running FLA batteries, I've had to add a scheduled load to consume some power to force a bulk charge (fridge by itself doesn't use enough) so the batteries don't stratify
If you're interested, I've written some Ruby scripts running on a Raspberry Pi connected to the PIP which push data into AWS so it can be monitored remotely. Gives some peace of mind being able to check up on things, AWS charges around $11/month for the small amount of usage.