So it's basically speedsoft.
Accidentally came across videos of it on YT before, being played in the Phillipines, and there are a lot of cheaters and stupid stuff going on.
Not to say the same would happen here though.
Looks similar to Halo Mill in that's it's small and a purpose built arena style and you have the opportunity to be fast paced and use tactics like that.
IMO it would be fun to play as a game mode but for me I'd rather just play ordinary airsoft and mix it up with elements of this.
Judging by the popularity of Halo Mill (although of course I would say advertising has played a key factor in the business - seemingly they have attracted a lot more newer players as, amongst other things, the site is conveniently open on weekdays) it probably would take off. I think it would be popular with younger players too, again because of the availability when compared to traditional airsoft and people thinking they need a lot of gear to start off etc.
Should mention I do prefer woodland skirmishes as opposed to indoor games at a place like Halo though.