I can attest to the spotty connection in Jbay, it really depends on how far you are from the tower. I'm in C-Place with line of sight to both towers so my connection's good enough. Vodacom 3G drops off every now and then. Until two years ago 3G signal wouldn't even reach Fountains properly.
Funny enough, roaming on MTN with Telkom was also better in my experience as well, although this was a while ago. I would use TrueWAN but their throttling policies are quite stringent and my ADSL line has been rock solid.
Off-topic, is there anyone in Jbay with a 10MB DSL connection? The exchange apparently doesn't support it and I know the connection between Humansdorp and Uitenhage is over WiMax, but my line definitely reports that it can sync up to a 10Mb profile.