The simple rule of thumb is to submit a plan. If you don't, then my response, unless my airspace is dead, will be "contact flightwatch on xxx.xx to submit a plan and call me when you're done". Radtags were not designed for this type of day to day operation. They provide no alerts and if it is busy and I don't pick up things aren't quite kosher, and something goes wrong, I'll be hung out to dry.
Sorry Spodman, I have enough trouble seeing 2/3 of my airspace due to excessive open windows (although the rules say I have to have 100% visible) without having to have another window open for someone who can't be bothered to submit a plan.
We are told it is a workload permitting service. The irony is that if we don't take on the VFR and something goes wrong, we'll be hung out to dry anyway.
R_S.