I don't have an S120, but I do have a P100. That is an all-steel compact. Every Tristar/Canik55 I have seen is built with close attention to fit, and finish. My P100 is an excellent shooter and I trust it 100% as my EDC. Accuracy is very good. The trigger is an acceptable combat grade trigger. Trigger and safety do require break-in. Both are a little stiff to begin with, but I attribute this to overall close tolerance the parts are speced to. Both do break in nicely. I recommend a regular oiling schedule because the fit is so tight. As it breaks in this may not be as necessary. I haven't tried it, but a good polishing might help. Upgrades for trigger, hammer, springs, etc, are available from Cajun Gun Works. CZ75 grips are a perfect fit, as are the mags. I wouldn't hesitate to compare Tristar/Canik55 firearms to pistols costing half again as much or more. I am very well pleased with my P100