There is a somewhat formless, subjective prevaling opinion that the AMD64 version is a little less stable than the i386 version under 0710. While this stability question has not really been thoroughly substantiated, there are definitely a small number of minor things that are known not to work, or be buggy in the 64 version compared with the 32. And given that in a product like LMCE 64bit really doesn't give you a material performance benefit, most people are just taking the simpler and safer path and going with i386.