This will be tubeless, just like Fluffy Kitten, and if it ends up released as-is will likely be the same price.
When I saw these comments I was all ready to launch into my "this is why I don't do tube versions of solid-state circuits" speech, because generally it either a) doesn't sound like the original circuit anymore or b) doesn't sound as good as a tube circuit could if I ignored the original circuit. A fine example there is Glass Clover, my 12AX7 Tube Screamer. It sounded better than a tubescreamer, but not as good as like a Dr. Wattson. I could design a better tube overdrive by ignoring the tubescreamer bits.
But when I go on with this speech, I tend to overlook a fine exception: Lab Rat. Lab Rat sounds better than a stock Rat, and frankly if you're looking for that flavor of dirt, Lab Rat is hard to beat, and replacing the solid-state bits with more tubes would no longer get you the sound I was after when I designed it.
So obviously a tube Klon is doable, but it becomes a matter of how you implement it. My first thought would be to replace the input buffer with a tube input buffer and add a tube gain stage to the output. Klons really shine (in my opinion) when they run mostly clean but with a high output level and push a tube stage into breakup. So it would basically be getting the typical Klon sound with a little tube-ness in the beginning, then would also give you the saturated tube sound at the output (could be switchable if you just wanted to run a Klon, more options).
Crap, I just designed another pedal, didn't I? There are too many damn circuits in this world that haven't been built yet