It's hard to tell. I downloaded the detailed information from the Ballfinger site and, in theory, it looks as good as you might expect from the technological limitations of the medium. What is not indicated is something that really separated the men from the boys in tape transport design and manufacture – jitter – or what was termed scrape flutter (or something similar) back in the day. The later Studer, Ampex and Nagra designs had it licked but the rest weren't really in the same league.
I suppose the key question, if you really want the hassle of analogue tape, is whether you are better off seeking out a twenty+ year-old vintage Studer A820 (IMHO, the best transport ever made – available from 2 to 24 track), add the problems of maintaining such a machine these days (obtaining heads, guides, bearings etc.) or buying something like the Ballfinger. Another question must be asked: can you get tape nowadays that is as good as, say, a fresh roll of Agfa PEM368? I know a few small companies are making recording tape, but how good is today's production compared to the time when it was a (small) industry driven by people with a lifetime of experience in making coated chemical products?*
Anyway, come the resurgence of analogue tape recording, I have a few Dolby SR/A units that I kept back for the purpose of handling old recordings. I dare say that their value will increase commensurately
* It was no accident that many companies which excelled in making photographic film also produced the best recording tapes.