I cannot quite see any logic in selecting, say, Smith tartan, if your name is Wallace.
I do, however, look less favourably upon the practice of choosing to wear a kilt of Scottish tartan in a version which is greatly at odds with the standards of Highland Dress accepted in Scotland. I think that is mildly insulting, because the Scottish tartan kilt-outfit is, after all, just that: national-dress.
Kiltedscot, are you saying then that a kilt is a National Costume and a tartan kilt should be worn properly or not at all?

And, do you really think that family/clan tartans today have so much validity as to necessitate the wearing of ones' family tartan to the exclusion of others?