My two cents as an amateur woodworker:
There’s nothing inherently less stable about a squier neck vs a custom shop neck (wood types aside) as it pertains to ‘how a guitar is regularly stored and played under normal conditions’ it could be flat, quarter or rift sawed and unless it was made with twisty grain from the get go (which would likely ruin it regardless of cut) once it’s dried, shaped and finished with a truss rod stuffed in there, you’d be looking at differences of a rounding error’s worth of wood movement between the ‘cheap’ one and the ‘velvet rope’ one.
Squier necks generally twist and warp because they’re (historically) bought by entry level players or as gifts for aspiring players. If they’re left to sit under a bed for 10 years or chucked in a closet with moldy old strings pulling on the neck for 8 seasonal cycles and then sold on craigslist to an unsuspecting SECOND new player, yeah those necks will have a higher chance of being a smoking ruin and flat/rift/quarter or whatever type of cut will make not one single lick of playable difference. They’re going to be useless regardless. Keep in mind, the type of cut might influence the amount a piece of wood moves by fractions of an inch. If something is going to move or twist a cm or half inch’s worth of distance, having ‘the best’ wood and reducing that twist to 5cm or 3/8ths of an inch hasn’t done a single thing except lighten your wallet on the front end. It’s still firewood.
So long story short, in my opinion. Buy a nice Squier (or whatever guitar floats your boat!) that you like the look and feel of and don’t worry about anything (provided it starts healthy) except taking care of it like you would do ANY of your other guitars. If you want to hot-rod it, fill your boots! If you like it as is, that’s fine too. The point is, to enjoy the guitar, and not worry about if it may or may NOT end up junk due to ‘reasons’.
Hope this helps and it’s not at all meant to be derisive or anything, we don’t know what we don’t know and that’s totally fair.
Cheers
