The PAKT systems looks well thought out.
There is certainly something to be said for having complementary equipment that is brand exclusive. I am admittedly very high on Tom Bihn. Indeed, when I one bag traveled this summer for 5 days to MV, I used a TB Brain Bag coupled with a now discontinued TB packing cube backpack stored inside with complete success.
Peak Designs, Aer, Tortuga and Nomatic are all reviewing well with integrated design throughout their respective lines. I do think that many of these boutique lines are approaching their pricing max given their not being sewn in the USA.
At this point, IMHO, if the bag is:
35-45 Liters
Made of a 500D+ tier one material
Uses YKK Zippers
Uses Duraflex/Peer fasteners
Has a lifetime guarantee (fully acknowledging that this is very brand dependent re what is “covered” and/or “excluded”)
It is going to do the job for a 5 day max biz casual trip so long as one gives some thought to wardrobe choices that coordinate and can be easily care for on the road.
If i needed more room and/or my trip exceeded 5 days, I am a huge advocate of a backpack/duffel combo completely avoiding anything with wheels.