All pitot tubes are located in the “cleanest” airflow possible, definitely far away from the propellor wash.
I canot see any reason why not to use Pitot Heat throughout all flights. It is certainly a “line up” item on the bigger aircraft I fly, both Cessna and Beech advise that this is the correct time to switch them on, it only takes a second to do along with the other few things I always do in an effort not to kill myself, like full and free control movement, sync the heading bug and flight director, anti ice if required, etc…
From the earlier post it seems like that’s over cautious with the pitot heat but some other hot items might not be so forgiving
Peter wrote:
That would be the opposite of the Socata annunciators, and IMHO not “fail safe” (partly because it would also be OFF when you turned off the pitot heat) but is easy to do:
Put in a test switch, too! 
Upmarket annunciators have a built-in push to test function.
Peter wrote:
Upmarket annunciators have a built-in push to test function.
So your annunciator isn’t really upmarket, then? 
No; mine are cheap – well as cheap as any Swiss switches are
A decent push-to-test milspec part is about $50-100. You get them in turboprops but in SEPs the budget is $5/switch.
from here
