Tbh I never really used to pay much attention to fret size when I got a guitar, but as it happens, all of my guitars have had jumbo frets. But just a few minutes ago, as I pondered whether I wanted a strat, I tried playing my girlfriend's Squier Affinity (at least she got one with an alder body . . .) which has ordinary sized frets. And it just seems hellish to play. I thought that bends would be considerably easier with it, just because it has .009s on it and I'm used to playing with .010s or bigger, but it was surprisingly difficult. So is that the main difference (as far as playability goes) between fret sizes? Larger frets make bends easier, like scalloping?

It was unpleasant . . . though what surprised me most was that it was the MOST unpleasant thing about a squier.
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Well... larger frets make it easier to play faster parts, plus its easier to play on the higher frets (above the 20th fret). My guitar has medium frets so its kinda harder to play faster solos that use mostly use the higher frets... But funny enough u can become more accurate using smaller frets as there are less space to fret.(thats just an opinion from my personal experience)
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It's a personal preference. Some people like the feel of low-height frets, since it makes them play faster and makes the sliding around less friction-y. Others go to the extreme and want super tall frets or even scallop their fretboards.

Myself, I like frets wide, but low in height. I can play around the neck must faster if my fingers don't have to fight against speed bumps on the fretboard.
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Thanks folks, I'll just put it all down to a matter of opinion. The constant bump-bump-bump of the slides does bug me, though.

Danno13 - Maybe it's just bad technique, but I can't seem to bend notes on the squier without the string touching the fretboard. And no, not bending notes by pushing them in.

PS: Now I think of it, maybe wide but low fret would help. Less space between frets to push the string in, and an all-round smoother fretboard . . .
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Large frets absolutely make correct bending techniques easier, as a greater clearence over the fretboard allows a better "grip" on a string. However, correct bending technique shouldn't involve the string moving closer to the fretboard.
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