I'm planning on framing my basement with metal stud (2-1/2" x 10' 25-Gauge Drywall Interior Metal Stud). I have XPS foam 2" attached directly to the concrete wall. I plan to leave a 1/2"-1" air gap between the stud and the XPS and the Stud. I will use a sill sealer under the metal track.
I'm not sure of the best way to attach the bottom plate to the concrete floor. I was debating on using tap con screws or a power actuated ramset. Would the nail go through the metal stud ? My guess is the metal stud will stop the head of the nail. I've seen the nails get shot 1/4 inch into lumber before. I would prefer the ramset for speed. Also I'm debating if I should also apply construction adhesive since I'm using the Sill sealer. I would have to apply it to the bottom and top not sure if it would help out.