I use the 22nd on the e string sometimes and miss it when it's not there. There have been times when I wished for 24 and a trip e, but it does start to get "crowded" if you try to do too much down there.
As another poster mentioned, scale plays an important role too.

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The quintessential sound of 60/70's R&R:
Fender Tube Amps
Gibson Guitars

The only reason I go past 12 is to get a different timbre or pitch on scales. The number of frets doesn't matter as much as the "feel" of the guitar IMHO.
(My Strat has 21 frets BTW)

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'07 Squier Affinity Sunburst Strat SE
Fender Frontman 25R
Boss DS-1 Distortion
Danelectro D-2 Fab Overdrive
Delta Lab Multi Effects

when use to play metal i spent 75% of my time up there.
now that im into blues im hardly ever up there.

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63supro
"The good thing is in a club situation, most of the patrons are trashed and really can't tell the difference."