Here is how I have mine set up with the Guide Lid and Native with details of how I've attached the Native to the frame using 6 compression straps. Note that the bottom of the Native can be attached directly to the frame with K clips but when you have the Native filled up and have a load between the Native and frame it's kind of weird, having the compression straps there to adjust the distance from the frame seems like the way to go.
I haven't used it in the field yet, but theoretically I love this setup. It takes seconds to drop the dry bag, you can pop the Native off in seconds if you want to drop the frame, it's light and has plenty of room for day gear. I keep my camp gear inside lightweight dry sacks anyway, but having a dry bag as the main bag is even more insurance. The only negatives I see are it's kind of tough getting in and out of the Native when it's compressed tightly with the dry bag underneath, and without a zipper you have to dig around in there to get what you want. I figure I'd keep gear that I'd be less likely to get to in a hurry, such as survival stuff, puffy, raingear in the Native, and more urgent things like first aid kit and snacks in the Guide Lid.
If you wanted to ditch the Guide Lid, you could, but it really helps suck the Native to the frame when there's no dry bag. Otherwise, there's some slack between the Native and frame. Easily solved by adding an extra set of compression straps or attaching the compression straps directly to the PALs instead of the tab loops. By attaching the compression straps to the PALs you can also really compress the contents of the Native if needed.
Weight (using manufacturer specs)
Native 17.2 ounces
Guide Lid 11.5 ounces (including chamber pocket 1.5 ounce)
Sea to Summit 65L Dry Bag 10 ounces
Total pack weight 26.7 without dry bag 36.7 with