They're both going to be at the same connection speed, but I can tell you that the Sidekick II's IP Relay program is going to be considerably faster. The advantage of SKII's program is that we can both see the conversation real time, so I can begin the response as soon as I see "GA." AIM Relay is choppy, and it still takes a couple of seconds after I have sent my responses for someone to get them. Allthough I wish the split screen option was available for SKII's program. Since it is full screen, the caller cannot type at the same time, although if you type while the operator is typing, keep typing, and don't worry about us typing. We CAN put the conversation in split screen and fully see the whole conversation as it should, without the interruptions, but with AIM, the responses aren't letter by letter, so we can both type at the same time.