My opinion (and it simply is an opinion as waxes and the very slight subtle nuances they leave behind are very subjective) is that Concours is not worth the extra money over for example one of the lesser Zymol waxes such as Glasur. Naturally, this is just personal opinion but here's my take on the reasons why...
Let us not beat about the bush first of all - if you've done the prep work with a machine polisher and burnished the finish to a high gloss with a fine finishing polish, this is the finish you are going to walk away with at the end of the day. A wax will add nothing more than a very subtle nuance looks wise, regardless of price and what it claims to be able to do, and of curse it will serve the main purpose of a wax and that is protection - something that Concours falls down on alas, we'll come to that in a sec...
Here's the results of just machine polishing on a Mercedes bonnet:
And here it is again after Zymol HD Cleanse and Zymol Glasur was applied...
Spot the difference? In photogrpahs, you really dont stand a chance of seeing any difference, and even in the flesh it is mighty hard as if the prep work is spot on, the wax is adding nothing more than protection and a very subtle nuance. My opinion of course, I know its a controversial one, but its just what I experience personally having tried out loads of waxes, incuding very expensive ones...
Now back to Concours - it falls down on protection? Well, in my experience, yes. I trialled it on my car this winter as a winter wax, and I had durability issues with it, finding it lasted only 8 weeks before sheeting of rinse water dramatically slowed - Collinite 476 was miles better as a winter wax, indeed Zymol's own Glasur seemed more durale to me. I was disappointed and wont be buying Concours again for this reason, and the fact that the nuance it does leave (a silvery reflective look) doesn't last long.
By contrast, Swissvax Best of Show leaves a subtle wettness to the finish - indeed its the only "expensive" wax that I find offers anything tangible over the "cheaper" waxes - but we are talking very slight here... Durability seems decent from it too, and it will be the only expensive wax I will buy again.
My 2p worth.