That's not a bad price to be honest.
i paid £15 per tyre and the tyres I bought online and must admit they are good tyres.
omce you've had them all done the difference in the ride is immense and noticeable straight away.
Do let your insurance company know mine didn't make a difference to the premium but I did ask them to make a note and a confirmation just in case which they were happy to do so.
let us know what you think of the ride once you e had them all done