Reverse double 4-bar Vs. Reverse double 6-bar?

I’ve seen that most (good) robots are using a reverse double four bar as their main lift but I’ve also seen weird reverse double six bars. What is the point in using a six bar rather than a four bar? I’m only asking this late in the season due to my team qualifying for worlds but in desperate need of a redesign.
Team 20785b is a good example of a reverse double six bar.

After talking with them before, I believe they have told me they will no longer be doing a dr6b simply because of it’s immense amount of tilt regardless of how much they’ve improved their build quality. I have a dr6b, but it took me a longgg time to get it satisfactory to my expectations, and yet it still has its drawbacks. In my personal opinion, as well as through listening to other members inside my alliance (20785B is one of them), I would highly suggest to either do a dr4b or a dr4/6b. A dr6b has too much slack, even when using joints that help with slack. It’s just not worth the time and effort.

The main advantage of a dr6b over a dr4b is that you get more extension, and extension is ultimately what determines stack height. There are some good examples of a dr6b from skyrise that had minimal slop, one of them being from 2587z. If extension is your issue then a dr6b is the way to go, but if you don’t need more extension to stack higher then a dr4b is easier to build with minimalized slop.

Either design can be very successful, as teams have shown. Our team recently changed our top half into a 6-bar, making our lift a blend between the two. It has much less slop than a full dr6b and the height boost is definitely welcome.

Thank you all I appreciate the help very much. You guys have all reaffirmed the fact that visiting the Vex forums is always a good choice!