My 2c: I'm new to pick-ups so also new to tonneau covers. My 2016 Colorado long box, bought the end of November last year, came with the "factory" soft tri-fold cover. The Internet tells me that this is a CAN$575 (before taxes) item. Wow! Anyhow, we have just had a really crappy, wet, snowy winter and I've washed the truck many times including HP water and can happily state that the soft cover doesn't let anything in to the bed. It overlaps the bed and tailgate rails to within about 1/2" of the outer edges and makes a great seal. I also don't get water mist up through the tailgate bottom or edges, apparently a common thing with pick-ups.
If there are any Vancouver/PNW memebrs of this forum that are thinking about getting a tonneau for their Colorado or Canyon long box, mine will be for sale really soon as I've just ordered a canopy.
Rick 2016 Colorado Z71 Crew Cab, long bed
BDS 5.5" lift, Fuel Vector 20x9 rims, Toyo Open Country AT II Extreme 305/55R20 tires
Bushwacker pocket fender flares