As the author of the original Tenderizer build has not been on MWO in about 4 months, and will most likely not be updating his post with the Smurfy link, I figured I should take what has been discussed a bit in his thread and post it into a thread that will survive the upcoming redesign. As Beneliusbob said in his post, the only reason to get a 5N is to do a 3xAC/2 build. Otherwise, you are limited compared to any of the other Dragons. The AC/2s provide a tremendous amount of ballistic DPS at a decent range, and the MLs + SRMs offer a small punch up close. If you're only using weapons in the ranges their designed for, you should be pretty fine on heat.
