Depends how much you want to spend.
I have 3 wet cutters -
A Norton Clipper - 180MM blade, 500 watts - around £300.
A Rubi ND200 - 200mm blade, 880 watts - around £398.00.
Also a Rubi Diamant D-260 - 300mm blade, 2000 watts, around £700 ( balde would set you back at least £150 for a good one.
There are som many wet Saws on the market, it depends how much you want to spend.
My mate has recently bought one of the new DE-Walt wet saws, think they retail at around £600 - very good wet saw also, think the blade is 230mm
If you are doing a lot of natural stuff, and high grade porcelain then it is worth buying a saw with a bit of Oomph !! Otherwise a cheapo Plasplugs or B&Q model should suit you fine for ceramic tiles.