Yes we agree. Although I can give you a few routes around the highlands that 3. is a problem even flying at none daft levels. Glen next to Nevis comes to mind.
As for 4 I will admit that maybe most ppls don't have the pleasure of bouncing around at FL140 in the crap dodging CB's on the wx radar for 2 hours. Trust me when i say it happens, and i will admit that its not likely to affect a PPL VFR pilot but it is still a possibility if it all goes pair shaped.
And a small note on GPS altitude. The whole point of 1013 and QNH settings regional or otherwise is so that we are all talking from the same sheet. ATC can seperate us we can work quadrangal rules etc. If say someone gos up with a knackard Alt and decides that the GPS altitude will do, it could cause all sorts of problems. In fact if I had my way altitude would be blocked on all aviation GPS's unless it was fitted with an encoder from the static. BUt unfortunatly nearly all these units are barstadised off a basic unit which is also used for surveying etc where they do want the altitude.
The real debate here isn't the units themselves its the promotion of the airmanship involved in actually using one.
If posts were answered along the lines of yes gps is great but good airmanship dictates that we don't put all our eggs in the one basket. For VFR flying its best to have....with a good roof... Fine. And if someone comes on and starts saying you mad using a GPS i will come down whole heartly on the side of using GPS as a cross reference to other nav methods.
I am not having a go personally at you.
But when posters come back and promote that GPS is the saviour of navigation. And report that they have never had errors etc etc. All it does is allow a false sense of security to develop in GPS usage.
Now its just to get someone at the CAA to see sense and produce a good safety sense on how to use them properly and we can all work together to promote good airmanship gps usage.
MJ