I used to own the B710 and then the B710 MKII.
Both units were beautifully built and offered outstanding performance; unfortunately, they were both plagued by mechanical problems related to the transport mechanism. They needed to be cleaned repeatedly and they chewed up cassettes like peanuts. I only used TDK and Maxell (Chrome or Metal), but this didn’t seem to satisfy the deck’s appetite.
If you open them, they make a Japonese unit look like a toy in comparison, but the truth is the B710 never lived up to my expectations.