Dude its crazy i was JUST about to post about this. I am on the verge of going exclusively round shaders for everything. Personally i find they are MUCH more consistent with far less skin trauma than mags. For me, in a sense i guess you work slower as in you cover less area but it goes in perfect on the first pass so i tend to be able to "move on" to the next area quicker and overall complete a tattoo in the same time or less when compared to using mags. I will still use mags here and there but i am definitely using majority round shaders. Great post man