I don't bother with a Sgain Dhu for day wear. As Richland stated, openly carrying a knife could be troublesome. Furthermore, a pocket knife is more practical.

I think a Sgain Dhu is more appropriate as a formal accessory. If you want something really nice, go with Rab Gordon. If you are looking for a stock item, check out the good selection of knives at the Scottish Tartans Museum.