These weights are really good. I'm not using all the available weight yet, but it's great knowing it's there for the future when I'm ready. It takes about probably 1 full minute for me to adjust both dumbbells, so it's a pretty quick transition. The grip hurt my hands first starting out but I'm pretty used to it now - there's a sort of metal webbing that can be a little rough on the palms. Also, the spin lock handles actually do loosen quite easily, so you might want to quickly tighten them in between each set. This would only be a problem if you're using all the available weights, however, because the spin lock would be right at the edge of the barbbell and thus it may easily fall off. Hasn't happened to me yet, but it's something to watch out for. Overall, I think these are great and I'm glad I bought them. You can't really beat the price, either.