If you can get to SeeWoo on Lisle Street (Chinatown), they have a Sanyo ECJ-FS50 there for about £75. It's in the basement.

We've been cooking with ours for over 5 years. Makes Japanese rice beautifully, slow cooks and steams.
I've used higher end rice cookers (you should see the one my father-in-law in Japan owns) and, yes, they are a little better. But not enough for me to fork out on one.