I remember being a kid, ordering the Arch Deluxe, and feeling like an adult eating it. I recall them having a promo with Ontario Lottery & Gaming for a brief period, where they came with a free lottery ticket. Was marketed as being the toy in an adult happy meal.
I also remember hearing the McDLT failed due to the packaging. Came out at a time when that wave of environmentalism was sweeping North America in the late 80s and early 90s. People didn't like all the styrofoam it wasted. It's why they moved all their packaging to cardboard.
I had a few McLobsters in either Maine or NE Canada, and I thought they were great. I remember them as lobster meat in a hot dog bun. Fairly simple, but good. It could be that lobster on the West Coast is somewhat of a luxury, so I was easily impressed. I must have had 20 lobster rolls from different places while I was in the area.
When I was in Halifax a few years back, lobster was everywhere, and cheap too. I seem to recall some fast food chain, maybe it was McDick's, selling lobster rolls here for a limited time. It's too expensive to use the real stuff this far inland though. I'm not a huge seafood fan though. Halifax donair is where it's at.