I just have to to throw in my two cents' worth.
I had been with Vodacom since my very first contract, back in 1996 (!). Still, for reasons I can't fully explain, I decided to move to MTN at the end of last year. It wasn't that Vodacom was doing anything wrong at the time, I just felt like a change.
Three months later I paid in mega bucks, had my MTN contract cancelled and moved right back to Vodacom. And I had to change my number, because MTN couldn't release my number before the contract period was up, never mind how much I paid in. But then MTN couldn't do a lot of things...
So I'm back with Vodacom, and very happy to be there. Admittedly, I've never had to have a phone repaired. But then again, I try to stick with the proven brands - Nokia, mostly. I've had one SonyEricsson, but that only lasted about eight months and it was toast. W880i, I think it was. So back to Nokia I went.
I also try to look for phones that don't have too many moving parts, like slides or flips. They break easily. And tiny scroll wheels and the like are just problems waiting to happen. If you pick the right phone, you're unlikely to have any issues. But I stay the hell away from Motorola and Samsung, for sure. LG's phones feel plastic and cheap, and my one experience with a SE product wasn't good.
With that said, I've been using an iPhone 3G since the beginning of the year, and I absolutely love it. Solid, with almost no moving parts, and if you don't mess to much with the firmware, it seems pretty stable too.
Anyway, the point of my ramble is that saying goodbye to Vodacom won't solve all your problems - it'll just bring a whole batch of new ones. And my personal experience with MTN was beyond shocking (billing issues, SMS messages coming through days late, etc.).
I'm glad that Motorola sorted out your problem though!