It may be disappointing to you, but DA is the biggest among those mice lol, along with Zowie EC1 Evo. Spawn is quite wide but on the short side. EC2 and Savu are overall smaller than DA. Savu's bump in its butt is more backward though, and might feel different from DA and is better for claw grip.
edit: Oh and btw, Mionix Naos 3200 is another big optical mouse, but it has "angle snapping" which let you draw straight lines more easily but it can be a drawback for some (it does not reflect your movement 100%)
edit: What was I smoking jeez, G400 is a tad bigger than DA and EC1 =/
Edited by raisinbun - 11/7/12 at 12:20am