I've used a lot of carriers in the past, currently using T-Mobile for my personal phone because it's the only one that gives me what I want. I rarely ever use my personal phone to call anyone but my wife and vice versa, we have a shared-minute plan with free calls to T-Mobile cellular customers, meaning we rarely ever use any minutes at all.
I've had Verizon and while they never were any trouble, they were always expensive. I could pick them up again as a bundle with my TV/Phone/Internet, but it's just not worth it.
I've dealt with AT&T and Sprint through work and both suck horribly, nothing but problems and they just don't care.