I'm on Clen for about 4-6 days, then on ECA for the same period. I'm dong EQ so I don't think it will affect me that much. Sust will probably increase your Blood Pressure and I know Clen will do this to. Therefor sust and Clen or ECA isn't always that good combination. If you like to hold fat away, just do the caffein 3-4 times per day and add some light cardio before breakfast for 30 minutes and you will be able to gain size while holding both water and fat away, or atleast minimize it.
I do morningwalks a few times per week and I'm gaining mass while holding fat down pretty good.