You are correct on the iTaste clearos. What you will get with it is a iClear16 clearo, which is a type of CE4 clearo. Not sure what kind of CE4 you are currently using, but I'm going to assume it is a single top coil CE4 clearo that often comes with the lower-end Ego series. Opposed to this, the iClear16 is also a top coil, but it has two coils (you will see four wicks coming out form top), which provides for better wicking.
I think I have a sense of what you are looking for. I make the following assumptions:
- You are using VV/VW mods
- You probably are not looking to rebuild coils/wicks.
- You're looking for something convenient and easy to use (screw on and use)
So yeah, under these conditions. Clearomizers are probably what you are looking for. As to what you will like the best, this is really a matter of your personal vaping style and preference. There are so many out there, but in my opinion those that have similar builds often have little to no difference in performance. The 2 most popular manufacturers are probably the Kangertech and iClear clearos, and both produce quality products. As a general rule of thumb though, the newer models of their products tend to be preferable to their older stuff, and there are a lot of vendors with huge back stocks of older stuff that they will try to unload on you.
I think you are on the right track with picking up a protank, as it is a quality bottom coil device as opposed to the iClear's. Assuming you are comparing two quality clearos, this is where you will notice the biggest difference: bottom vs. top coil.
In my experience bottom coils deliver a cooler, lighter draw, and deliver more flavor. Top coils deliver warmer, tighter draws. Dual coils generally also produce tighter draws but more vapor than single coils. Top coils are slightly more prone to dry hits, while bottom coils can more easily be flooded (gurgling).
Here are some clearos that I would recommend from each category.
Top dual coil
iClear16, iClear30, iClear30s
Bottom single coil
Kangertech Protank 2, Kangertech Evod 2
Bottom dual coil
iClear 30b, Kangertech Protank 3