Great trailer and I recommend it without hesitation. For what I need a trailer for it works perfectly. The other utility trailer I owned was the Yak BOB and though nice was a pain with the specialized quick release and one wheel etc. I have also owned two other brands of kids trailers that were great when my children were little but a little wide when used as cargo trailer.
First the attachment mechanism is so simple and yet works so well. Easy on, easy off. The attachment is very flexible. I flipped the trailer once, but this was 100% my fault. Coming down a hill, jumped off a curb, took a sharp right and the trailer flipped. I rode it out until I could stop, the trailer stayed attached and the mount did not break. Right sided the trailer and rode off. If you don't do anything stupid like I did, the trailer is quite stable.
As you said it is easy on and easy off and this helps facilitate the trailer as a shopping cart. I use this trailer about 50% as a shopping cart. For anybody that has used a bundle buggy and if you are moderate height, the bundle buggy hits the back of your feet because the handle is not long enough. The Burley has great long handle that keeps the trailer far back from you.
The bags that I chose were the market bags and they work great, again for what I use it for. I have used it on my commute a few times when I have to take a lot of clothes into work etc but my main use is weekend stuff with my wife.
My favorite part of this trailer is the fold. It is so compact and fits into it's own bag. I live in a condo and space can be tight so this feature of folding makes it worth the money.
What I don't like, and not because it has given me any trouble are the wheels, which are made of plastic. Though they are functional, they just look cheap and they don't seem to hold air very well and with the weird shaped valve it is awkward to fill the tires.
Small complaint, nothing is perfect. If I lost the trailer, I would buy the same one again. Again, it has to fit your needs depending on what you carry. For me it is mostly food and for that it works great.
Do a search on this site and you will find other reviews. Hope that helps.