Our agency has 2 net guns. They are cheap and really kinda dumb (not the idea ... just the product). The few times we used out in the field, we would literally be standing there and the net cartridges would just deploy without intention. They are 1 use only cartridges so you have to buy more after each shot (I believe they are somethin like 20$ per... dunno, thats not my thing)
Save the money in my opinion, but you won't know for sure unless yall try yourselves
Cool idea though.