Well...I've been using them (on and off) and a few others for quite some time now.


Here's my takes on QDs and spray waxes.
I only use QD (M34) for clay lubricant and also (Last Touch) for light cleaning when/if I missed some spots AFTER WASH. I don't feel comfortable using it to 'clean' light dusting after a few days, regardless if the car had been driven or not. I just let it be and leave it that way until my next proper wash.
If I were to do (which I very seldom need to) that kind of 'cleaning', I would prefer to use a 'no-rinse' or 'waterless' product instead. For these, I would alternate between Optimum No Rinse, Duragloss Rinseless Wash or Megs D114 - Rinse Free Express Wash - my current favourite. These products are more economical to use. I use at 2oz to 1gal dilution (around 1:64) in a spray bottle and spray liberally or at 1oz to 1gal (1:128) if using a wash bucket.
M135 also I only use occasionally for spot removal of stubborn dirt marks or when I see light water spots had started to form AFTER A PROPER WASH. Like I said before, M135/Ultimate Quick Detailer is loaded with solvent and it cleans these type of contaminant really really well. But again, mind you, it could also strip or weaken the existing wax/sealant.
For Ultimate Quick Wax...now...this one is a good topper, and also use it AFTER WASH.
And here's my suggestion. If you were to start with one product, I would suggest you get the D156 first. Very rarely that you would need to do a round of QD after a good wash unless there's something wrong with your washing. And also a QD won't be able to do much on the appearance side. D156 would be more suited and meaningful to use after a wash, to top up the protection and amp up the gloss. To tell you the truth, before I have the glass coat on my ride(s), I use to top up with one form of spray wax or another *almost* after every wash

And do consider using Optimum No Rinse or DG Rinseless Wash (these two are locally available) if you decide to do those 'in-between wash' cleaning instead of using a QD. They cleans better and *maybe* safer as these were meant to be use as a light wash instead of just for *light* clean up.