Picked up a Gillette Slim Adjustable on ebay. One door is a bit lazy, but it closes snugly so will give it a soak in soapy water and a clean with some Cif and see how that works. First adjustable so looking forward to experimenting with the settings!
RE: the lazy door -- it's hard to tell exactly from the photos, but in your second photo where the doors are open, it appears that where the door "ears" engage the base plate (TTO opening is a camming action) the door on the left isn't fully engaging the base plate (almost appears past it) which usually means that either the push rod is bent/out of alignment, but more likely it was dropped and the base plate is either bent down/up on one side. There are threads on here on how to fix either the push rod or base plate adjustment up/down (I've used the method using a butter knife/flat bladed screwdriver to much success) -- you also want to check to make sure the gaps are good which if not corrected will make it shave more aggressively/harsh on the side that's out of whack.