Nah... more than likely blowing smoke up your rear end, to try and get you to switch to a more expensive brand. Like I said, I use Coralife in my mix... and it's perfectly fine. There were very few problems reported in that thread regarding all of the salts.
Trace elements (other than Ca, Alk, and Mag) were also reported to be insignificantly different from brand to brand.
So if Coralife fits your bill, as far as what target water params you shoot for, then keep it. If one of the other salts on the thread catches your eye, or looks to be closer to where you would like to keep your water params... then by all means, make a switch.
The main goal as I stated, is just to try and find a salt that closely matches your target water params, so that minimal buffering is needed.