For an inexpensive, easy to use applicator, that E1 thingy rules. Of course I prefer MF applicators to anything else but they ain't too cheap.
I've used the E1 app for PPCL, SMR, and a couple other polishes. The yellow grip part takes alot of pressure off your fingers which makes the job less tiring to your ligaments and muscles.
IF you're going to do all your polishing by hand then a couple E1 apps are great. Do your final wax/sealant steps with something softer.