The price on the etha has dropped to 350, so it's now 150 dollars difference. Currently the etek is more upgradeable, but the etha is the better marker for the money. I think right now the etha should be the gold standard for new player(or someone who is has no gear and is getting back into the game) markers because it comes with grease, parts, tools, a hard carrying case, and a nice 2 piece barrel(i think the etek does too, but just saying, a lot of markers don't.)
My local field won't shut up about the empire axe and it is 460 dollars with no carrying case, no tools(just a parts kit) and a barrel that most anyone would replace immediately. People have complained that there are no upgrades for the etha, but it's a new marker. They already have violent triggers, rampage board, techt bolt, you can do a POPS ASA on it, the emc frame for milsim attachments if you want them.