At the expense of efficiency & usability... which doesn't happen in Evolution.
The "efficiency" of Evolution remains to be seen as not enough details have been released to evaluate it.
Efficiency can't ever be measured, or even defined, without comparing benefits relative to costs. Higher or lower costs in and of themselves do not equate to higher or lower efficiency. Bitcoin, for example, has orders of magnitude higher costs than traditional banking, but Bitcoin provides (at least some measure of) censorship resistance which banking does not. Thus Bitcoin can't be said to be "less efficient" than banking because it isn't even doing the same thing. Likewise for these other systems.
Any form of mixing will carry a cost, so we will have to await further details to see how that cost plays out in Evolution, and compare that cost to the value of the benefits delivered.
Also, I realize this is an old post but it was quoted here so I'll respond to it:
CryptoNote has just ONE selling point.
Without anonymity it's just a terrible Bitcoin clone. Imagine Bitcoin with such a bloated and slow blockchain...
CryptoNote does not have one one selling point, and it also isn't "bloated and slow" compared to Bitcoin. If you look at the white paper, section 2.1 addresses privacy but sections 2.2, 2.3, 2.4, and 2.5 address other shortcomings of Bitcoin addressed in CryptoNote, including efficiency. When compared on an apples-to-apples (equivalent functionality -- see above) it is faster and more compact (section 2.5).