What is good for the goose is good for the gander, if you have other than anecdotal data that can provide proof that the mini (one inch face) gages are any less reliable than a standard spg I would be interested. I did drop one with the full weight of the bottle behind the impact and it cracked the glass. Then the glass popped out at 100 feet, this being on my solo pony, but the gage continued to work, just another anecdotal story.I might not feel comfortable using some cheap off-brand tiny knockoff button gague. But if you wanted to use something like that and wanted a more reliable solution, just use a regular SPG on a 6" hose. Yeah, it's a bit more money, but much more reliable and more flexible in terms of mounting for optimal visualization.
Regarding TXs and SPGs in general, I doubt there is any "study" that would prove or disprove one being more or less reliable than the other. An SPG has a spool with two O rings, the TX has batteries and electronics and can be subject to interference. Seems like an even trade and if anything weighted to the advantage of the SPG. That being an opinion based on anecdotal observation.