Adrian, I use a Dr-2d for what you're doing.
I run Busman bsc1 > Tinybox (providing p48) > dr-2d mic in.
Also SBD > dr-2d line in.
It works really well and it is a perfect solution for very little money.
I have recorded a bunch of shows that way with no issues from the SBD being too hot for the line in. I have never had to have the soundguy turn down the signal, but having a couple of attenuators can't hurt just in case you need them.
I have 10, 20 and 50 feet runs of RCA>miniplug cable that I use depending on how close I can get to the SBD. If the SBD doesn't have an RCA out, I have a bunch of adapters I use (XLR female to RCA female, XLR male to RCA female, 1/4" TRS male to RCA female, 1/4" TRS male to stereo RCA, and some various other adapters. If you spend 40-50 bucks on a bunch of adapters from b&H and a decent rca/miniplug cableyou have every situation covered.
Not sure if you can find a dr-2d around but they were going for under $100 for a while. The only thing I don't like is the battery life. I can only get about 4-5 hours from a fresh set of alkalines recording 4 channels. Usually a fresh set of batteries for each show/night I record, not a big deal but much shorter life than the battery life with the M10.
The R-26 from Roland is a nice little unit but much more expensive.
Good luck with your choice.
Here are a few recordings with the dr-2d using SBD + ambient mic sources:
http://archive.org/details/acresandacres2013-02-02.busmanbsc1.sbd.flac16 Acres and Acres - nice acoustic set, sounds really good.
http://archive.org/details/jinxthecat2013-05-04.bsc1.sbd.flac16 Jinx the Cat - jam/rock, mix is a bit bassy at the beginning then gets dialed in.