As you say, pro's and con's.
For me, top concern was driving safely: with balanced wheels (esp front wheels), with safety at speed over 60-80kph (depending on road surface), and unlimited km range before swapping wheels back. The higher boot-deck setting still leaves useful space under the deck for tools tarps etc. For daily use, the higher deck setting is actually easier to load and unload, and adequate.
I have heard of others using a japanese model of space saver - but do not recall which make-model.
As for goop, I am told it can lead to early retirement of the damaged tyre as it can prevent future puncture repairs... and clog the remote pressure gauge.
I had to use the spare within the first 1,000k's - thanks to a tradie's dropping a box of tech screws.