I dont know if it will hurt the finish on your guitar. I believe the finish on Avalons is a bit more delicate than typical, but you'd have to ask JB that. Regarless, I never have used any string lube on any of my guitars. Just dont want to goober them up. I would think that putting that stuff on would deaden the strings. You might want to try some different strings instead. Those EXP's that Avalon uses standard are surprisingly smooth, and there are some others mentioned on this site (nano's) which are supposed to be very smooth too. I had never used EXP's prior to receiving a new Avalon, and was surprised how smooth they were. Like I said, I never used a string lube before, and with these, I cant see any reason to.