Unfortuneatly I don't even have a way to look at the 3 colors without mixing them up, but haven't found a need to, I have mixed some variances at times to compare and the prime formula has always been the way to go. So with that said, even though I should maybe spend the thousands on the color books and $500 or so every year for the updates, I just haven't seen a need to do so.
And the few times we have had to tint or adjust a color, the times I have mixed a variant, I ended up tinting the prime for best match.
Also even if their was a rep in chicago, their would be no guarantee that he would have the color chips. The new ones were just released over a month ago.
This has been the biggest downside to pro-spray, the customer service and the lack of color chips. Now they have the color chips but I don't see all the jobbers jumping on purchasing them at the cost.
The biggest reasoning I would see to purchase the chips would be to see the color variants for custom paint jobs or when you want to alter from a original formula to get a different look when doing a job, but for the everyday match, prime is the way to go.