I had this happened with all brands i ever bought. Barts,Overton,Polyform,from Ed,from skier to skier...Whatever branding is on them ,some always turn sticky and craking on top,sometimes the entire set will go bad.
Best ones i had were from Overtons about ...20 years ago!
We just put a new set every season and keep the best ones as spares.
I've never tried Wally.