I wouldn't have thought this would be a problem. If you're trying to record, the playback quality isn't going to matter, and if you're trying to mix down, it should work with everything coming off the repro head.
The only time I can see it going bad is if you need to monitor both the record head and the playback head at the same time, but I can't think of a situation where that would be the only possible way of doing it.