For studio monitor stands that are both sturdy and adjustable, I highly recommend checking out IsoAcoustics stands. They're considerable for reducing vibrations with their built-in isolation technology, which should help in improving sound clarity in your studio. The ISO series offers various sizes that can support different weights, including models suitable for your 15-pound monitors. Many of these stands also feature height and tilt adjustment, allowing you to position the audio sweet spot precisely to your ear level, which can significantly enhance your mixing accuracy. I've used them in my setup and noticed a clear difference in sound quality. Investing a bit more in these features is definitely worthwhile for any serious home studio setup.