I've been spinning for years and personally, I don't wear my cycling shorts to spin classes. The classes I take are only 45 minutes, so I can endure without the need for a chamois. Plus I do other stuff at the gym on my spin days, and can't imagine working out in padded bike shorts...that would be WAY uncomfortable for me. Not to mention the weird looks I'd likely get. However, I DO use cycling shoes and would definitely recommend it. When I first started spinning, I was wearing my regular running shoes and would always get hot spots and numb feet due to the flexibility of the shoes. By switching over to a stiff-soled cycling shoe, I eliminated all those issues. I use MTB shoes with SPD cleats. For the road, I use road shoes with Ultegra cleats.