I need to buy a new brush for my AG pool. Are nylon bristles longer lasting than poly or does it make no difference? I have read that the Whale Wall is a good brush but seems to have some issues with corrosion. Also, I need a brush now and the Whale Wall isn't available locally. The blue and white brush has poly bristles and is available at Walmart for $15.47. The HDX one has white nylon bristles. I can get that one from Home Depot for $16.98. I would appreciate opinions on which one is the better choice. Thank you in advance.