I've had an ID for about 10 years now, with various brain cells for various Mac laptops. My current 2016 TouchBar MBP really didn't fit well inside it, so I decided it was time for a bag upgrade.
I ordered a Cadet (Burnt Orange/Northwest Sky) with a cache, an absolute strap, a Side Effect (Mars Red/Canyon) [not a "Sidekick" as I wrote in my thread title], a set of zip pulls in case the zip clinking annoys me!, a set of gatekeeper clips so I can try modding my old ID to take the cache, and an extra 8" strap. I had it delivered to a friend in Denver who met up with me in France last week. So I thought I'd post some early comments after a week's use.
Cadet
The colour. The burnt orange is slightly not what I expected from all the photos. It is definitely an interesting colour, not dour in any way, not bright and gaudy either. I like it and it is really growing on me! Very autumnal, maybe. My wife says that it is currently a very trendy colour, so I've accidentally become trendy. Yay :-)
The cache works pretty well. I'm not sure what more you can say about it, except that the memo that you don't have to remove laptops at airport security hasn't reached Lyon Saint Exupéry.
The carry handles are a welcome improvement on my ID's pretty unpadded handles. They stand up quite stiffly so are easy to grab, and I like the amount of padding.
I've opened the rear zip to slip it over a rolling suitcase handle, which works fine. It does make the whole affair quite heavy, so I reverted to the absolute strap after a while.
The little central "phone" pocket on the front is a little tight for my iPhone 7. I guess it might loosen up a bit over time, but honestly I mostly keep my phone in my hand. At a pinch, my passport fits. But I discovered that it is a great little place for storing things like security badges or hotel key cards. That alone stops me from having to check all my (too many) coat pockets for my cards.
I fill the main compartment with the cache, my Apple PSU and USB-C cables in a padded organizer bag that I bought a while ago for my ID. Our funny plugs here in the UK and France do make this a bit bulky. It attaches nicely with a short strap to an organizer ring, so is really easy to slip in and out and not get lost. I also have a moleskine notebook in the main compartment. I have a USB-C to displayport video cable lurking in the main compartment pocket, and I can slip my Kobo Aura One ereader inside too, which is about the size of the moleskin/an iPad Mini.
I haven't put much inside the front flap yet apart from my mechanical pencil. I put my UK and Euro wallets and coin purses in there, which took a bit of arranging to balance out.
Side Effect
I bought this because a friend was bringing my TB order across from Denver to France so I'd avoid the expensive international shipping and extra customs charges, so "why not" get a Side Effect too! BTW he was really impressed with the build quality so you get an extra sale out of this ;-)
The colour is nice and deep - you had me at Mars and Red anyway. The finer weave of the material suits it.
I haven't yet figured out how to use it. It feels slightly like a "man bag" which doesn't bother me too much, but if I attach it to the Cadet via a strap it tucks away and adds a bit of extra organization. I've tried putting my wallets and pills and things inside, which definitely keeps them all nicely together inside the Cadet front flap, but that bulges out the Cadet a little. Trimming down the wallets will definitely help. Fewer pills would help too, but well... The hack on the forums here using some small karabiners/clips to turn it into an in-flight seat pouch looks interesting, so I'll try and hunt something down.
I might repurpose the Side Effect's hand strap so it becomes my security badge lanyard.
Absolute strap
This was one of those things that I wasn't sure was going to be as good as it is. Lovely and squishy on the shoulder, and it really helps carrying the cadet around. It is super comfortable, and I wish it would fit my original ID! (It won't as my ID doesn't have the hooks.)
Photos to come when I find some spare moments and some good lighting!