Stan,, Your profile doesn't say where you are located, but a 5 yarder might be just the thing for a warmer climate. The 8 yarder is going to give a much better pleat effect. More of them, options on pleating to stripe or sett, etc.

Also, how are you going to wear it? Dinners, weddings, and céilidhs? Or at local highland games, pubs, etc.