I was told that I could avoid being too much hassle by:
1) Listening out for 30 seconds or so
2) Call XXXX123 requesting practise PAN.
That way you're unlikely to mess up a real emergency I think, opinions?
As for the commercial traffic, up there I listen to 121.5 all the time as well, and I've found out that using the volume button can help the distraction of a practise pan! Also I've learned that thesame volume button can subsequently negate the problem often found after the practise PAN, namely having 121.5 turned off. The volume button should be described in detail in your flight manual
.