That's like asking which scale is the best... there is no answer. Imagine a solo played entirely with legatto or entirely with sweep picking... :confused: Good solos use a mix of techniques such as alternate picking, legatto, sweep picking and finger tapping, unless it's a once off display of a particular technique. IMO the most important technique to perfect when starting is alternate picking, after that everything else falls into place.... except sweep picking (I wouldn't bother with that untill you are an accomplished player).