Hello, I am looking to choose one of several small bookshelf speakers that I own
Um, if you own them why are you asking us??? Just listen to them and pick the ones that sound best with your music. If it’s me I’d go with the ProAcs because they image/soundstage and disappear extremely well and are very musical so will likely sound good to a wide variety of listeners. The Sierras would be my second choice, but again it really depends on what you like more than anyone else’s opinion.