No matter the lever, keeping the tire in the rim bed where you aren't currently working on it is key. Sometimes you think it is, but it isn't. Then I'll see that and fix it by putting it back in the bed, and it gives me that bit extra.
I use the pedros. Usually just to get em off quicker. Working the tire into the bed usually makes it so I can get it with fingers. Well, if the fingers as dripping in sweat on a hot day.......back to pedros!