I thought they were great until they wouldn't replace a faulty part unless I sent it to them for "testing", knowing full well that my car would be off the road for as long it took them to test it. I'll never use them again, and was particularly unimpressed when the guy on the phone said "oh, I've never heard of an expansion tank being faulty..." . Yeah, WHATEVER!!
You can't be an internet trader, with all the cost savings of not having a store etc, and then have a crap returns policy.