I got a flat (actually, my tire exploded as I was wheeling the bike to the door) last month and used up my last tube. I remember when I bought the tubes the guy at the bike shop asked if I had long or regular stems. I wasn't sure, so I told him what bike I had (Specialized Dolce) and he got me some long stemmed tubes. What's the difference? Are regular stems that much shorter? It just seems harder to find long stem tubes, and they never seem to come in those multi-packs that Performance and other sites have. Can I get away with regular stems?