Regulation lost a lot of it's "magic" for me.

[FuzzyGrub]

But I'm also thinking a lot of it is becasue folks like to practice/plink/play with their hunting rifles, and getting more shots extends the play time between fill ups.  Doesn't really change the air use, are just running up a larger 'air pressure debt' for that longer string of shots (in money-debt terms: are exchanging 12 small payments every month for 4  big payment every quarter).

No interest on those bigger payments, though.  In fact, a very slight reduction, because less waste in refilling the hose.     

I can tell you I'm not going back to pumping for each shot!   

[Ribbonstone]

And I'm more of a pay-as-you-go guy...we get to about the same place.

[triggertreat]

I've got no issues with regulating my .25.  I have been able to get 32 shots at 51.5 fpe and 24 shots at 55 fpe.  Both tunes are under a 2% ES.  I find both tunes great for plinking or hunting.  As long as the accuracy in there all is well with me with regulated or unregulated. I like the 50 yard and beyond ranges and find my tunes very accurate and fun to shoot with reasonable shot count for both.