Sorry I was not discounting any issues that you were/are seeing. I was mainly just highlighting that 3.5G is more just a higher data rate channel with in the 3G/UMTS system.

Some of your questions revolve around mobilehotspot which is somewhat more complicated (than I really understand) and I can fully understand where processor speeds and overclocking would have an affect, after all the handset is routing traffic from one interface to another.

I can also understand when a redundant APN could have some impact when using mobilehotspot/teathering especially if it is not able to detect the APN stauts properly. I myself have seen issues when teathering where my PC is trying to use on APN and the handset is using another.

I believe you said you were on Wind (Canada) mobile which is still a relatively young network, so may still suffer slightly from growing pains.

Again sorry I'm not much help, but with out mobile/cell network traces its hard to really see whats happening