Some good advice above, especially Heavy Duty, since you ride 2up most of the time that would be a necessity.
I run 440 HD shocks usually on the next to lowest setting and it gives a very good ride 2up. We are under 350 total and around 400 with all our touring gear, I crank it up 1 or 2 notches when I have the tour pack on.

 

Putting Ohlins shocks on my 06 StreetBob was one of the best upgrades I've done to the bike. I can ride solo sport or 2-up touring. No bottoming out. Adjustable to compensate for weight and style of ride I want. MotorcycleMetal.com has a line of Ohlins shocks at different prices and good service. Anything you spend on suspension will be an investment you'll see paying dividends every time you ride. Good luck. Jay