or is it better to do as many tiles with a score n snap

For ceramic tiles, yes, but a decent one if possible. I have a Rubi but
it looks like this works on a similar principle.

http://www.screwfix.com/prods/64932/...e-Cutter-445mm

where the score handle also does the snapping, so that you only position
the tile once. Doesn't sound that important but, after 40SM, you'll
appreciate the benefits in terms of time and accuracy. It also easy to
mark and cut tapers, which IME usually form the bulk of cuts.
The edges are perfect (and therefore sharp) but, as these invariably go
into a corner or behind skirting or whatever, it doesn't really matter.
I usually do the tricky cuts manually with a diamond disc on a mini
grinder (IIRC there were just 2 on the last room I did, so it wasn't
worth setting a saw up outside for that).