drigget-
I would use Touch as a light maintenance product every week, as you are doing.
Express, in my mind, would come into play every 4 weeks or so. With a base layer of Poxy already existing, Express is going to bolster the existing protection and add gloss. You could keep adding Express once a month to your maintenance schedule and continue this until you feel a need to detail the car (wash/ clay/ polish/ Poxy) without much worry about degraded protection during said span of time. Express is pretty darn durable for a speed wax. I wouldn't necessarily categorize it as a spray wax but now I am getting into semantics and that doesn't matter.
When applying, keep Express THIN, spread it briskly, remove it immediately. You should be able to apply it to a mid-size sedan with 10- 12 (possibly less) trigger pulls out of the sprayer and that includes priming your applicator with one spray first.
Best regards,
-Gabe