Any iPhone 3GS users having problems with 4.0?

Got this mail in from a reader…

Ewan, hi

I am struck by anecdotal reports of 3GS users who have updated to OS4 saying that their phone now regularly reboots 3-4 minutes into a call, so much so that they need to use another phone for business calls as Apple provides no way of switching back to OS3.

Have you picked this up? If so, it is a really damning fact for Apple’s QA, and completely undermines the idea that “our software works”.

I have upgraded both my 3GS and my 3G iPhone and both appear to be functioning ok. Has anyone else experienced a similar issue?