I have used the new AI adapter for countless fills with absolutely no problems.

its up to you on which one you buy. They both do the same thing.

Ive only used the AI ones. But I dont trust the plastic they got now... buddy had one and snapped the tip off pretty fast, he went back to using his V2 or v3 adaptor by AI

The metal tip ones will bend if dropped and the plastic ones break off. The AI duster adapter (comes with the kit) can be used as a replacement provided the whole thing didn't snap off. I have an AI one myself and love it but the Madbull ones do the job as well. Don't drop your tank and you'll be fine.

I was just going to say the same thing.

Nothing is wrong with the plastic one. Aside that yes if in clumsy hands it will break. As long as you are careful nothing will happen.

Using mine since the Summer, I must have filled almost over a hundred mags by now and hope to fill more.

Also on one note the AI Propane Plastic Adaptor did so well that now you can find copy cats of it from other Airsoft sites. But I'll keep my Canadian invented product thank you.

I have dropped my older version (metal) AI adapter countless times on objects which would snap off any plastic tip. Its going on 3 years with no problems... i think the only thing thats going to make me a buy a new one is if i lose this puppy.