First, I should scold you for not googling "bottlead", as the company's web site is the very first link that shows up.

I use a Bottlehead Foreplay pre-amp, with a homebrew gainclone power amp (see photo). I am very happy with it.

I think they make great kits. Many people use their SET kits with Pi speakers --> the high efficiency of Pi kits, especially 3pi and bigger, makes them very suitable for SET, either 2A3 or 300B. The thermionic series is specifically designed for tube amps, although I've seen Wayne recommending the theater series as well.

• http://www.bottlehead.com/