I had the original AI adapter (metal, two part v1) for years, it was great; until I accidentally knocked my propane bottle off a table and it landed nozzle first
By then all the AI adapters were plastic and I went through two of em (under normal use, no propane bottle swan dives or anything) in less than two seasons. The tip of the probe developed a crack/chip on both, eventually splitting or breaking.
Looking for a metal adapter, I got the Madbull one with oil port (which had just come out at the time). I've been using it for about 5 years now, I think. I've been using GBBRs only for the past 3 years, so its being used for more than just the odd pistol mag now and then. Very happy, no complaints. The oil port is sorta handy when you have a lot of mags to fill but its not particularly faster/easier than just unscrewing the whole adapter so its not vital.