Use the tool that works best: if the singer wants a handmike and performs better doing so, let the singer use the handmike he/she likes. One big advantage is that the singer is already familiar with the use and can get physical while doing the track - instead of standing neatly in front of the mic stand with pop screen. Some examples of people recording with a dynamic:
Bono (U2) - Shure Beta-58A / SM-57
Steven Tyler (Aerosmith), John Lennon, Sufjan Stevens, The Killers - Shure SM-57
Björk, PJ Harvey - Shure SM-58
(BTW, Shure SM stands for Studio Microphone!)