It seems that many Tannoy retailers have an extra air of arrogance about them. I know, i dealt with one two weeks ago and not for the first time.
Ignore what they said about requiring a high powered amp. Your Yamaha receiver will be just fine. A friend of mine recently bought the Tannoy Saturn S6s for use with his Denon 3802.
Just note, the DC1 is not a very efficient speaker whether it is the Sensys line or the Eyris line (many bookshelves tend to be less efficient than full sized towers) such that your actual sound volume limit will be attained a bit sooner than with other speakers such as Axioms.
It seems to me they have discontinued the Saturn lineup and it appears as though your choice for the new Eyris models are the replacements.
Come back and let us know how things sound once you get all the parts in place. I would love to hear about the Eyris speakers.
"Those who preach the myths of audio are ignorant of truth. Research begets reality."