First, that power supply doesn't deserve to be marketed as a 460W power supply since it barely can deliver 312W on its +12V rails. (Newer designs of power supplies can deliver up to their entire rated output on the +12V rail.)
Only a minority of PSUs, most of them premium models with a premium price tag, advertise PSU output entirely in terms of discrete +12V capacity. The norm is still total power = ALL RAILS based on a particular cross-regulation load assumption, with +12V only accounting for a fraction of it.
This is how most multi-rail DC power supplies (of almost any type) have been labeled since forever, but only became an "issue" when a lesser-informed purchaser came along who didn't know how to read a PSU label. If you look back through the discussions from several years ago, even with reputable brands like Sparkle, Antec, Seasonic, Enermax, and others, the complaint was always
"Total advertised power is n, but if you use the load limits per rail given on the label, and adjust for group limit (if given), it only adds up to 85% of n!" So that was never unique to or an indicator of cheap/inferior PSUs.
I've used about a half-dozen Elite Power 460W and Extreme Power Plus 500W models, I still have a couple of them NIB, and its true they are overrated. I don't treat them as true 460W or 500W designs but they're not junk, either. If you take a decent 400W PSU design and market it as a 550W model, it doesn't turn it into junk because it can't do 550W.
I treat the 460W models as though they are more like ~380W designs and the 500W models as more like ~420W. For the price that I paid (~$30 after rebates with free shipping), they're as good as anything else for that price and actually better than some.