I rather detest colorful mats and to a slightly lesser degree colorful frames. Black or white mat only. I'm sometimes tempted toward gray but I always talk myself way out of being so wild.

I associate color matting with cheap prints. I understand and am not judgemental about sculptural frames, they are just not to my taste.

I will add that I prefer an off-white to stark white which I find too cold and harsh. For a high contrast print that demands a stark mat I like black.