Most clearos will leak if you do something wrong. Some are designed with a little more wiggle room for operator error, but if you get a seal not seated correctly, or overfill - it's going to leak.
As Chimney34 said (wisely), maybe get two different types to see what will work for you. Perhaps an EVOD or a T3S and something like a vivi nova, CE5 or iClear30 - just so you can experience the difference between a top and a bottom coil.
Everyone will have an opinion and offer it up (just like I did!) but sometimes the only way to find a clearo that you like, that you can trouble-shoot and that you enjoy the vape from, is a matter of trial and error.
Just remember, you sometimes (always?) have to fiddle with most delivery devices before they a) work correctly and b) get the vape that satisfies.