Thanks guys. I really don't mean to drag up any old arguments!! I'm satisfied that each may have their own favourites, all with good reasons too. I'm more looking for what to watch out for - the "gotchas" given that I have zero experience of the colour heads.
Anyway, I have the transformer sorted and intend hooking it up to see if the bulbs are OK. If they're not then the experiment will probably die right there!