Yes, as Nick says, that makes much more sense than just two wires from the block. In that case, I would DEFINITELY go for an XLS and the chunkiest Visaton speaker you can fit in the space available (with a spray-can-cap enclosure over the speaker, works a treat). It'll run fine on analogue (and sound great), gets over all your lighting voltage problems, and will be all ready for DCC when you decide to make the leap.
If the XLS prices over here are a bit high, try this chap in Germany:
http://stores.ebay.de/stebaorg?_trk...ervice and very easy to deal with.
Jon.