I've been testing Outfox since yesterday and i'm getting some mixed feelings.
Granted i only tested it with one game (R6 Siege) and my current connection probably can't be improved in any other way (LTE wireless) but besides that the experience has been somewhat confusing to say the least.
Firstly, i can't sort preferred Outfox server by ping, All i can do is make an educated guess based on real life distance between my location and location of the server, which does not always equal to improved experience (Frankfurt servers are technically closest to me however i've been getting best result with server that's in same location as current Siege gameserver (Amsterdam))
Server selection is quite limited, especially if you live in any country to the west of Germany and east of Japan. Personally i live in Poland so yeah - it'd be a great thing to have at least single server here, especially since biggest ISP in the country has really tragic routing and unless you have fiber connection from them (which most don't since it's not available in most private locations) you're third class citizen with connection that's not suited for gaming at all.
Using "fastest server" option doesn't work as intended for certain games. As the choice is done based on initial connection the game makes - like Siege, which arbitrarily connects all players to a server in Canada before actually pushing them to their "nearest" datacenter, which means most of the time "fastest server" function will usually either opt to not use Outfox or assign wrong server as fastest.
Session detection seems wonky at times - one time it doesn't detect the game running and other times it doesn't detect the game is no longer running.
Inconsistent behavior - While using best Outfox server i could find, pings somewhat decreased from 100+ to ~80 which would be actually a bit of an improvement if it wasn't for inconsistency of the improvement. It jumped back and forth between 80 and 100 for seemingly no reason (i don't get that much ping variance with default connection).
That's all i found out for now during my limited interaction time. As it didn't really offer any substantial improvement for me i doubt i'll be buying the service after the trial expires, but i guess leaving feedback won't hurt.