Many (but not all) BIS CDs are well recorded and mixed. They are not minimalist recordings but are clean. If you get them as downloads from eClassical.com, you can get a refund if you don’t like a particular release.
Oddly enough, given their origin as the low-priced label, Naxos has released some excellent-sounding recordings. The series of Malcolm Arnold symphonies was recorded by Chris Craker with a minimalist technique. Most of their guitar recordings -- I am thinking of the Laureate Series -- are recorded by Norbert Kraft, himself a fine guitarist and someone interested in minimalist recordings.