I recently went back to using a 9 or 10 day "week" for my training schedule (so that you have at least 3 days rest between similar workouts and 4 days for back and legs), and I find that this helps tremendously.
Regarding the X3 bar, besides seeming wildly overpriced, I would strongly recommend getting some basic bands to start with and see how you do. Bands are tricky to have the right tension for the range of motion and it varies greatly from person to person. Start with the $15 walmart bands and evolve from there. I like to use bands or chains with barbell work.
I also added in sled pulls and higher rep work along with the lower rep work which also seems to help a lot. I have become very into sled pulls using my home-built weight sled. It lets you combine sprinting with mild strength work. A great workout between heavier weight days and it's easy on the joints and very cheap to make.
