Glad you got them Tom, aren't they amazing! In my mind Tannoys are grossly underrated by the hifi buying public.
Richer Sounds Glasgow also gave me a £30 refund for the ad that took them down to £119.99. WHAT A BARGAIN!
My near 10 year old Denon PMA-255UK (35wpc) is running them, BUT the F4s must be extremely easy to drive as the amp hasn't faltered at all delivering the loudest volumes I like to listen at, and still sounding great at very low volumes as well!
Still breaking them in with everything I can get my hands on out of my collection and they can deliver everything I'm throwing at them with finesse and power when it's needed. It's like rediscovering my music collection for the first time.
I too wouldn't mind going up to something like the PM6002. But also take a look on eBay for amplifier bargains, you could probably get something worth alot more for a good price (currently searching for various Roksan, Linn, classic Pioneer, well in fact looking at anything I can drive to that might do the job and go for stupidely cheap prices!)