Ok, in terms of action, how low is low? My setup is (.09 gauge):

6th string: 2mm
5th string: 2.3mm
4th string: 2.5mm
3rd string: 1.5mm
2nd string: 1.3mm
1st string: 1.2mm

What kind of action would this be? I'm trying to cure the fret buzz I get on the middle frets (around 5-9). I put a straight ruler against the neck and it's slightly concave (as it's supposed to be, right?) There's around 1mm gap between the ruler and the fret in the middle.

Sorry for the wordiness, I just can't tell whether the fret buzz is coming from my fingers or the neck. Considering I played acoustic for ages I thought my fretting was pretty firm.

Also would you suggest raising or lowering the action for lots of legato playing? I'm gonna get the guitar professionally setup since I got it secondhand.
You can judge your action based on how it feels to play. Do barre and open chords ring clean? Can you bend the top 3 strings up a tone without the notes buzzing or fretting out?
Yeah I can bend everything fine and the chords ring out cleanly as long as I press down firmly but there's always a slight buzz when I lift off the strings to go to the next chord or note. It's not too noticeable when playing quickly, but you can hear it at moderate speeds.
i had to get the truss rod adjust on mine(and some bridge work)
i had the same problem you do but worse
there was fret buzz on all frets of the g string no matter how i played it
the neck was "curved" or whatever. but it didnt cost me anything to have it done.
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A lot of times, especially on cheaper guitars, it's a matter of compromise No buzz=too high, perfectly low=too much buzz. Part of this is building your hand strength and fluid movements to reduce the transitional buzzing too, but you also may simply not be able to avoid a little buzz if you keep the action at a comfortably low level.

edit (assuming the truss is adjusted properly. How much clearance do you get at the 6th fret when you hold down the first and 12th frets simultaniously? Should be around the thickness of a credit card.
If it's buzzing more around frets 5-9 there is not enough relief in the neck. If you don't know how to adjust a truss rod don't do it yourself. You'll f**k it up and may actually break the rod. It's easy to break it. Then your axe will be a club.
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