I've got two SMK208s... Both in .22... One, is I believe standard but shoots really well and is very accurate and the other is the TH, thumbhole stock model which I believe has a Diana 34 piston and trigger fitted and put together well.
It also shoots beautifully and I would have no hesitation in recommending them... Maybe I just got lucky, but I reckon they're worth checking out, particularly second-hand.