Generally, though, I don't think most of us actually mention the Q8 in a thread that also has vinyl or reel--the latter are more likely to take precedence. If I have vinyl and Q8 and detect any significant differences, of course I'd mention that in my review.
But yes, if you go to the 4-Channel spotlight thread that I moderate, you should find enough about Q8's--I hope. When it comes to quad a reel tape would be anyone's preference, I would think, followed by either CD-4 or Q8, which are discrete formats. When one has an SQ or QS and Q8, the latter is the format I'd reference if I have it, since that will by default be more discrete than the vinyl.
ED