As no one else has been along yet:
I've never had a Chinese tube amplifier 'kit', but I'm sure one or two fishies have.
They look reasonable and affordable, but watch out as most are for 220 volt mains and are over run on 240/250 volts in the UK. Burnt out transformers or short valve life could result. Don't expect high power, the quoted outputs are optimistic(!), or hifi results. Over on the diyAudio site there are a few threads on ebay kits.
I assume you are talking about a power amp, so have you looked closer to home at the World Designs kits? Their KEL84 is at least real hifi when finished and there is a good forum for support.