I'm not a fan of the bench type double seats. Storage and transport are the big problems. And not being able to move easily from front to back of boat is another issue. The individual swivel type seat works best for me. Unfortunately, the one I use is no longer being made; Add-A-Seat. If I were buying now, I'd get the Sidekick from Millennium Marine. Best price I've seen is at Grizzly Jigs. https://www.grizzlyjig.com/p-502-sidekick-fishing-double-seat.aspx
The other option I'd consider is from Cumberland Crappie. http://www.cumberlandcrappie.com/DoubleSeatMount.html
Considerations are what type boat you have and ability to see once the boat is on plane. Double bench seat up front will block your view when running any style bass boat. The other two types above can be partially or totally removed and put back easily. If you have a center console with wide front deck, either style may work.