i had that done to the big toe on my right foot because i was getting ingrown toenails. i was awake for the whole thing though, they just froze up my toe and cut into it. i don't remember how long the pain lasted but i don't think it was too long or too intense. i got a cortisporin dropper (antibiotic/cortisone) to prevent infection and increase healing speed.
as far as aesthetics go, my nail doesn't look too bad. i was worried at first because it looked really thin, but they cut off more than they burned off so when it grew back it was a bit wider than when it was fresh out of surgery. it's still noticeably thinner than my other toenail but it doesn't look abnormal, and people only notice something when they're side by side.
i hope all goes well, it should be a relatively painless procedure, just make sure you keep it clean to avoid infection.