BIOS updates are NOT to be considered like 'driver updates' for any stretch of the definition. Sure, some BIOS updates solve fan/temp problems to random BSOD/shutdowns, but if you aren't experiencing any of those problems currently with the version you're on, then stay with it! These 'updates' exist because of production dates on outgoing units where minor/major manufacturer changes in FW exist due to the order of batch 'field' testing with variety of OTHER components and hardware throughout the assembling process. This can be contributed by a test engineer or through end user feedback as later units are still being shipped.
It's not only risky in some cases, but imposes major downtime if something goes awry and you don't got means to correct it. I can say that I've flashed every version of BIOS available back and forth numerous times on my G751JY, mostly without issues using either Easy Flash, AFUWIN or FPT. You just need to be sure your system isn't overclocked, overvolted, undervolted, on battery only, during stormy weather, frequent power outs, random restarts or shutdowns, etc. There is still a chance even when all that is taken care of, that the BIOS boot block still gets corrupted from flashing to another version of BIOS (whether older or newer). You got to expect the unexpected.
So, to the question, will you notice a difference updating your system BIOS? Unlikely, unless it's addressing the fix in question you require.
I do a lot of BIOS/VBIOS modifications and not everything goes according to plan (although mine is mostly just through modifications). I've had bad flashes because of the nature of the modifications I've done which caused me to use my programmer on even my 980M (W25X40CL) SOIC BIOS chip and even my system SOIC BIOS chip (W25Q64FV) because of it. The point is, I have no worry as I can always correct this.
So I suggest for you to have a backup plan is all I'm saying before proceeding with updating BIOS (if you feel so inclined to do so now).