I found the IPMS Stockholm list more of a starting point than an end. At least with the Tamiya colors they recommend the closest color, which is not necessarily a match. For instance, for Sea Grey RAF, they recommend either Tamiya XF-53 or XF-54. 53 is a little dark, and has no blue in it, whereas 54 is close to US Neutral Gray, with no blue, and is quite dark. The Polly Scale line and the Acryl line are not listed in this guide, which I am sure is being updated.