Disclosure: I retail Tannoy Prestige, Departure Audio.
You put it best in your original post - "I'm a little burnt out on hifi." Tannoy's are a final stop. IMO, It's not really relevant to compare them with other speakers. Other speakers will measure better, spec better, image better, etc. but that's not what Tannoy's are about. That big, fat, juicy, whole, gripping, emotional presentation of the music either gets you or it does'nt. The cliche that it's about the music and not the sound is really true in this instance. The magic is due,I think, to Tannoy's 80 plus years of refining the fundamentally correct dual concentric technology. There's something magic about a dual concentric done right that can't be replicated by other approaches.
My bias is that if you can fit a 15 incher, do it. Also try to spring for a model with the alnico and pepperpot. I demo the Canterbury SE's.