To take a stab at a bad analogy here, that's almost like saying "I'm willing to get a TOTL Tesla, but IDK if I like Hybrids". By which I mean OTLs have a stereotype for sure (warm & gooey), but there are a lot of factors that can change the sound. Whatever info you might glean off of listening to one OTL, won't be indicative of what you'll hear from a Glenn, or many other manufacturers for that matter. That's not even touching the tube rolling aspect. IMO, your best bet if you want to hear what a Glenn (or Woo, or whatever) sounds like is to find someone with a Glenn. Not an easy task I know, but I don't think listening to a Darkvoice for instance will tell you much about what a Feliks OTL would sound like. Good luck though...keep us posted!