Wonderful!
I have been living with the Mullard 3-3 monoblocks now for quite a few weeks and in every respect they are an order of magnitude better than my previous amps and they were still very good. With music the sound is very natural with a complete lack of veiling and artificial treble that is often apparent with solid state amps. They actually sound more powerful than my old 150 W monoblocks. With movies the same is true you tend to get 'a real cinema sound' when the volume is cranked past halfway. Friends and colleagues of mine who have heard them agree that they sound excellent for ~3 W per channel and ~£300!
I think they address one of the problems not often talked about in the hifi community. Certain pieces of equipment can sound very impressive on first hearing. However the more you live with it the more you tend to realise that the sound is something that long term you just cant live with due to its artificial nature. I think Mullard had it correct all those years ago when they produced amps that people could live with and listen to every day without fatigue. Although I carried out a couple of minor mods to the circuit (bypass the main reservoir caps, install a resistor from the HT to ground in case of tube failure etc) essentially they are identical to the original Mullard specification. I am delighted with their performance and although it is not necessarily a project I would recommend for first time DIY'ers (due to the voltages involved etc, confined working environment) I would certainly recommend it as extremely worthwhile. Peter the transformer 'guru' at F+S transformers has produced a superb transformer and chassis kit design which certainly does the circuit justice. It is not often in the audio world that you come across bargains but this is one of them!
F+S transformers are based in the UK and can be contacted on 0121-686-2939. They also make transformers for other high quality audio applications such as the 5-10 amp etc.
Happy listening!