we're with Axa, via the RSPCA and managed by BDML....
So far so good, been with them for 6 years - currently paying about £27 for Millie (10 years) and £24 for Jennie (8 years). 6 years ago I was paying around £25 combined, and slowly it's increased, though to be honest I don't think the increases have been extortionate and because they have always been so good, with the lifetime cover for Jennie's ongoing eye problem I've never been worried about moving (despite some nice cash back offers and some 'cheaper' deals).
We get £6500 per condition per year, it's lifetime cover and has a £75 excess ... no complaints, really pleased with them, best insurance company I've had to deal with, so fingers crossed they pay out Jennie's rather large spinal surgery bill ....
Not a big pet plan fan - 6 years ago they wanted £30 per dog for less cover than the RSPCA / Axa were providing.