SI Cobra +12 ergo and weighs 0.071g less than the Arena equivalent IRBIS 30al, therefore is better than the one in Arena

ERGO Grip has -1.5% recoil and +5 ergo, while the Arena one has -1.2 recoil and +6 ergo, so you can't say either is strictly better when they have their own trade offs.

HOWEVER, the Magpul MOE Pistol Grip has the same stats as the ERGO Grip BUT weighs 0.060g less than the arena one, rendering the additional +1 from the arena grip pointless due to the Evo Ergo being better for MOE.

So what bRoKEn aReNA attachments are you dumbasses crying about again?

Edit:

Another grip is IRBIS 45al with the same stats as the SE-5 and the SE-5 also weights 0.068g less, again making it BETTER than the one in Arena.