Which brings me to a question - How come the Epic has such a large volute and the Essence basically doesn't have one at all? Is the Essence neck inherently stronger so it's not (as) necessary? Even after trying an Essence for a minute, I found my left hand to be far more comfortable and less strained when playing low fretted notes.
 
EG

Hard to answer this precisely. The simple answer is that set necks (Epic) come standard with volutes, while thru-necks (Essence) do not.
 
It's not the overall strength of the neck itself, but rather that the thru-necks - which require much longer pieces of wood - actually use a scarf joint to attach the peghead to the neck, and then also have a bunch of laminates (top, bottom, and sides) that reinforce it.
 
There was a nice discussion of this recently, with some photo references, and hopefully someone will come up with the link (oh, i guess i just did).
 
If you're willing to pay the price, you can get either a set or thru-neck with the opposite configuration. Personally, I also find the volute to be a bit distracting.

Bob; I've just added it to the Must Reads.  Thanks!