Depends on what one does. If I'm meeting w/ entertainment industry clients I don't need them. If I'm meeting w/ corp America or am working a trade show, then I do. I like the idea of 1 size up though. I was in LAS earlier this year for a show & had forgotten to pack some extra Calvin Kleins. Went to hotel gift shop & they had some cheap pair. Bought my size & they were the small/miserable that prncss674 mentioned.
Cheers.