The upgrade is the benefit. Sitting on unsupported OSes in todays security horizon is at best risky at worst idiotic and foolhardy. Yes the E10 uplift is a big nut to crack but sitting on old software is a great way to get hacked. I remember a statistic that something like 30% of companies that get hacked in a serious manner due to outdated server OS never truly recover and some similar number completely close shop if that hack is a CryptoLock. So if your backup solution is iron clad (no ones is) then go for it. Live on a risky OS. Personally I’d rather live safely. Ive watched several E10 uplifts from E9 (and Vantage) with folks that I know (I am the IT guy not the Epicor guy here, so I support the OS and Systems for Epicor not the interface itself), but it seemed to be a reasonably decent process. @jgiese.wci (our Epicor guy) might be able to give some advice on how the Uplift went.