I have an 8 year-old Freepack City which I still use although it's a bit worn out. I also have a newer Freepack Meta II. Both are great for carrying the laptop + adapter + book and more stuff. The Meta is larger though. I use the bag on my everyday commute and it's great.

I had the Klickfix truss in the past but now have the Dahon one, it's made of metal (aluminium I think) and IMO it's more stable, but both are ok.

One of the benefits of the Klickfix system is that it is Ortlieb-compatible. I also have an Ultimate 5 bag that I can attach to the truss.

Oh, and by the way I also have some speed bumps on my route and the truss handles them quite well :-)