yeah, the laney lionheart is nice, if you like class A amps and don't need more wattage for big gigs. i haven't tried the H&K, as i said, so can't really compare them. machinehead had a deal on the 20 watt head with the 2x12 cab, i think, if they haven't already sold it.
my only concern about the koch (and this is from only trying it once, quite a while ago) is that amps which can get to the highish gain stuff often still have that tightness when you turn the gain down, which prevents them from sounding truly vintage (from what i can remember, when i tried it, the koch sounded a bit too modern for me, as i was also after a vintage-ish amp at the time)- i mean, the screamer can be run at lower gain too, and i'm assuming that doesn't sound "vintage" enough for you? just would be worried that you buy another amp which is very similar... :lol:
are you only playing at home? if so, a cornell romany/romany plus or plexi (haven't tried the plexi- assuming it's of similar quality to the romany plus i've tried, it should be good though) might be worth a look... only the romany plus has reverb, though. or those martamps which twinfan is always talking about, they look really nice (and good value) too, but i haven't tried them. advantage of the martamp would be that you can get exactly what you want...