I've been using RG55 for well over a year now...I really like the product. It's ease of use is on par with the best of them, while providing superior durability. My experience with it is limited to Audi's Sprint Blue, Nissan's Carbon Silver Metallic, and BMW's Jet Black. The look...to each his own, but I found it share top billing with respect to depth, wetness, and durability. I still need to try it on some really flakey paint for a better opinion...Carbon Silver Metallic, isn't a great sample.
Race Glaze just came out with their new flagship wax, Signature Black Label Concours (£275.00), supposedly at 66% carnauba content by volume...but at that price, I'm less inclined to try it since '55' is so good for 1/4 the cost, but interesting sure enough.
One thing to note, '55' has been known to sweat a lot out of its jar initially. So, if you're planning on getting some, store it in a zip-lock bag for the first month or so, until it settles. Then you can just wipe it clean and store it normally. Of my 2 jars, 1 sweated a lot while the other hardly any.