I just got a type-s and to be honest, I personally prefer it to BT................sort of
If they just came out with a Type-S BT I would never look back, I'd pay 500 if they asked it. That kind of stems from my paranoia when opening up HHKBs. I've never bought an HHKB that was modded, or I modded myself, that didn't feel worse, to me , than a stock HHKB. Take that with a grain of salt, as I'm very much like that with everything, and it's most likely mental.
I prefaced with that to say that, the BT overall is a much better experience IF YOU DONT MIND THE NOISE. It's more well built, the case design itself is a bit more refined, and I'd say the key feel and tactility in my experience was a bit better, most likely due to the case redesign. If you're comfortable with stock HHKB noise levels, or feel like you could silence it without effecting the key feel, go for the BT for sure. If sound is a big thing for you like it is for me, I'd suggest the S.