interesting question you have, I thought I am the only one with this stupid problem. I will give you the whole story if you allow me.
Bought a used Switch kite some years ago with a Best bag. Looked like this bag was recycled from an earlier model to be used for this kite from then on. Anyways the zipper became stuck at some point and had some holes in the bag - time for a replacement.
Easy going, I thought. Some days of research and digging I found it is hard to find replacement bags for kites. I ended up buying two of these bags and I love them. They are not perfect for me, but they are great!
https://switchkites.com/collections/acc ... te_bag_un5
They have everything any other bag has, plus some unique features. Internal! bar compartment but separated, little storage for keys, pump valves, etc., they are expandable with a zipper, nice and thick shoulder straps, two thick compression straps to mount your board to or get the air out of the bag, mount your pump horizontally on top of the bag (unique). What I don't like is that they don't have any compartment on the sides on the outside, but that is about it! Have them in use for 2 years now and no issues quality wise. I even think order 2 more to put the in stock because I think they are great engineered and quality.
Bought a Cabrinha Contra some time after the Switch bags and couldn't fit it back into the original bag. No matter how carefully I tried to fold the kite, I always ended up getting frustrated and force it back in. No good! You want to give your kite some air to breathe if you will. At least I like to handle it that way. So I use the Cabrinha bag from now on for the 9m kite, and the Switch bag for the Contra. Another benefit I believe comes with it. No one will steal a Switch bag, when there is a Cabrinha, North, Core bag close to it
An even more unique design I found was a RRD bag
https://equipment.robertoriccidesigns.c ... ories-y25/
I have not gotten my hands on those bags yet, but the design idea behind it is very interesting. But I wanted a bag, a simple bag. This is why I chose Switch over RRD.
In addition, for travelling I bought 2 different compression bags. A Mystic, and a noname. They have their place in the world, but they are not as comfortable and have way less functions than common bags which the kite comes with in the first place. I will use them for air travelling because they do the job, but it is a very specific use case for those - my personal opinion.
Hope that short overview helped. If you find another brand or product which you like, I am happy to learn from your experience.
Edit: I just realized that you posted this into the 2nd hand forum. I don't have one for sale, but if want to buy a new one, now you have some options
Should have read more carefully in the first place.