A friend of mine has the 9105 which he imported (originally a T-Mobile UK handset) and he loves the phone. He had an iPhone 3g for 2 years, then up (down) graded to the Xperia X10, and swiftly moved away from that (abortion) after only a month.
He is totally happy with the BB. He doesn't like QWERTY keyboards, so the 9105 is perfect for him. Its like a normal phone, with the advantage of blackberry. The screen is also brilliant, and the battery life is astounding!
MTN has said that they will be receiving stock at the end of October...