The Cloth Room works pretty well these days. Back when it was introduced, in Poser 5, it took a lot of processing power compared to the average machine, and there were often serious memory issues. There are still occasional memory issues, but overall, it's not too bad.

If you buy or download dynamic clothing, it generally comes with presets set by its creator. You don't have to mess around with the settings unless you want to. I guess choosing these presets requires some knowledge and experimentation, but I doubt it's more difficult than creating conforming clothing.

It's the Hair Room I wish worked better. Heck, I still haven't found Superfly hair shaders I really like.