Thomas Shey
Legend
I found that for me, and my group, it's considerably slower, due to communication issues, and worse with the VTT up instead of just a dieroller. Without body language and facial expression, it's much easier to miscommunicate.
I assume from this you mean the VTT doing mechanical support? Because I can't say I've seen any sign moving tokens around a VTT maps is any slower than doing the same sort of thing on a battlemap; if anything its more forgiving.