Changing telephone/ADSL supplier

We're a bit fed up with the high monthly charges we have to pay Movistar for ADSL - particularly as I don't think we get a very high number of megs (is that the term??) and it can be slow.

A couple of years ago we tried to change from the then Telefonica to ya.com and it was a nightmare. We ended up without telephone or Internet for three months while ya.com tried to change. We'd been instantly cut off by Telefonica but ya.com were unable to reconnect us. It appeared that Telefonica were causing problems, but we're not really sure. I had many difficult, technical phone calls in Spanish mainly.

So my question is, can anyone give details of a good experience they've had changing from Movistar and which service providers people can recommend please. The last experienced almost caused a divorce and we dread having the same pesadilla again!

Thanks.