I went to Redhill and from a cockpit management point of view it was easier to note the range/bearing to a consistent VOR/DME station.  However, SD used CPT, then OCK and finally BIG and I didn't want to retune and identify 3 separate stations.  So I selected Midhurst (MID) as it gave me the best range/bearing from a single source.  

Could have used Biggin (BIG) instead but the point is it would be easier to use a single RNAV for a particular phase of flight rather than the arithmetic closest which changes 3 times while doing a zone crossing and final phase of flight.  

I suppose my point was if the PLOG RNAV vectors is just the arithmetic closest and so could be against different VOR's on a route, it is really very useful then?