[quote name='alhbass' post='717772' date='Jan 19 2010, 01:02 PM']I used to use a Markbass LMII, and now have an LMK. I'd be willing to bet you'll find a 500w MB head plenty powerful enough! These days I have MB cabs - but for years I couldn't afford them, and so used the MB heads with all sorts of cabs, including various Ashdowns, and, for a while, two Trace 4x12s stacked. I can honestly say the MB heads have always cut it, even at big outdoor gigs. I was (and still am) playing five strings basses too.
I heartily recommend you give them a go anyway, if you're after a good, lightweight amp.[/quote]
I think I have found a way to (legally) sidestep the US tax and export rules which will allow me to source a Genz Benz Shuttlemax 12.0 for around £650 so probably going to head in that direction.
These amps seem to get some great reviews. I like the fact that they are VERY light, you can blend the tube and FET preamps, the headphone jack can be easily used as a in-ear-monitor for when there is no PA support and the 12.0 has a very powerful and flexible power section.
Shame we can't get them anywhere near as cheap as they are in the US ($1099 vs £995!).