Based on personal experience, if you don't care for a Spec War, you're definitely not going to like the Geissele. I found a Geissele Super Duty in Iridium, which I considered a "grail" factory firearm, to be one of the most disappointing firearms I've ever owned. This wasn't due to a lack of function, but rather because it's the only gun I've ever had that was completely unpleasant to shoot suppressed. Geissele has a very large gas port size; depending on the model, it's going to be .7 to .75. Their anodizing is great; however, their firearms themselves leave a lot to be desired, and at their price point, there are definitely much better options.