I compared my ride to a dump truck before replacing front and rear with Progressives.
I tried Progressive 440's in the standard spring and they bottomed out with anything other than myself on the bike, and I'm 200lbs. Heavy duty springs are a necessity for anything that isn't stripped down to the bare minimum for weight.
I returned the 440's for HD418's and they are perfect for me. I believe the key to them being so comfortable is that they have adjustable damping as well as pre-load. The front are the standard Progressive fork springs, they only make one replacement set.
Whatever you go with, I do recommend Heavy Duty springs if you ever plan to ride two up or load it with travel gear. Otherwise you will be hitting the bump stops over any decent size road bumps.
Adjustable damping is not available on alot of aftermarket shocks and I strongly believe that is a huge plus to finding your comfort zone under all conditions. I think Progressive discontinued their line of 418's, but some may still be available. They were less expensive than 440's and have totally exposed springs rather than being partially covered with a shroud. The pre-load is adjustable just like the stock shocks with the stepped notches, and comes with a wrench for the adjustment. The damping adjustment is at the top of the shock and has a small plastic key-ring tool for turning the adjuster dial.
I don't know what Williams was referring to about stockers being too soft ... he's the first I know of to refer to Triumph shocks being too soft.

Everyone prior has compared them to not even having a rear suspension or complained of the bike bouncing your butt out of the seat over harsh terrain. I know my ass left the bike over even the smallest of pot holes prior to replacement.
Good luck, shop and compare as much as you can ... ask the seller if you can exchange them if you aren't happy. Summit Racing is where I got mine and they have a liberal exchange policy, FYI.