I have turned up at several airfields un-announced, without telephone PPR and never yet had any problem......If I remember I'll give 'em a call first, if I forget and they won't let me land I'll take my business elsewhere.
If I'm going to a"big" airfield (the sort that make your orbit for 20 minutes becasue a 737 is on a 10 mile final) then I'll phone and arrange it beforehand, at least then my 90 quid landing fee looks like its been for something worthwhile...
EA