I'd go with enan over sust anyday. With sust, you're not really getting the full benefit of short esters cuz there's not much of it and to have to pin EOD when you can do two per week of enan. To me it's a no brainer... If i want enan to kick in sooner, i can frontload by doing EOD for the first week, then twice a week after. With sust, it's EOD for the whole cycle.