In my experience, pelletized hops absolutely have to be bagged to avoid screen clogging during the transfer, especially at the quantities used in IPAs. (intrigued to hear about Visor's experience with the Trub Trapper, though -- I've been thinking about that lately, and it's good to get some real world feedback on the device).
Another good option is to make (or buy) a hop spider -- I use it frequently for my brews with lots of hops, because I can just keep dropping the additions in over the course of the boil without ending up with a gazillion little mesh bags at the end (or having to pull out a mesh bag from the boil). A few tutorials have been posted online for DIY models, and they're pretty quick and easy to assemble.