Although I'll admit to having owned a pair of padded spandex shorts once, almost all the riding I've ever done was while wearing cotton shorts. This includes several extended tours. These days, I do wear cotton briefs under the shorts because they improve comfort. My current favorite riding shorts are "Land's End" brand that I got for almost nothing at Sears. A nice soft khaki without a lot of extra pockets. I also weigh 150-5 and ride a Brook's saddle. I also wear loose shirts. A silk/linen blend bought on sale is my favorite. I think Spandex is partly explained by the need many people have to feel enclosed, packaged. Just my humble opinion, of course.