I don’t own the LV’s so I can’t offer an opinion on those. I have owned a YSL and the quality was horrible. I think others have had issues with YSL too. So check that forum.
I, do, however, own the 3 Chanel styles so I’ll weigh in there.
Bottom line - I adore my Chanels!

They’re beautiful, functional and versatile. Depending on the size and style, I can wear them casual to dressy. (Probably not formal for the styles you are considering.)
Chanel caviar jumbo - This is perfect a go anywhere / use anywhere bag. Caviar is pretty sturdy. So you don’t have to worry about rain or a minor bump. I prefer the look and feel of lambskin but it is more delicate. And the quilts on lamb are more likely to deflate. So if you like the texture of caviar, it’s a great material.
These are best worn with the chain doubled. I’m tallish at 5’8” and can just pull off wearing it single chain crossbody.
These are large bags.They’re a little big for dressy occasions IMHO. I think these look best casual, work and cocktails.
Also, if you are petite, try them on to make sure you like the look. That being said, my 5’ tall, 95lb daughter rocks the heck out of my jumbos and steals them whenever she passes by my closet.
My only issue with the bag is with the double flap version. I think it doesn’t hold much relative to its size. So, I do have one double flap but, I actually prefer the single flap jumbos (now discontinued) and buy them preloved.
That being said, if the perfect color was released, I’d definitely buy another df jumbo
Chanel flap bag - Hmmmm...I’m not sure which one you mean so I’ll make an assumption. Are you asking about the M/L? I do have one of those in lambskin. These bags are sooo cute! You can easily wear this casually but, moreso than the jumbo, you can easily wear it to dressy occasions as well.
The double flap on this bag means that, yet again, it doesn’t hold as much as you’d think but, I can certainly get in enough for my needs: sunnies, card holder, makeup pouch, tiny medicine pouch, gum, tissues, pen and misc.
Chanel Boy - Ooooh my! These are fun bags. I think they are / were a great update to the Chanel line up.
They are all single flap so storage is good and they are easy to wear.
They come in a variety of sizes so you need to pick the one you like. I’m a fan of the new medium for every day / general use because I like storage (obviously) but I also want to get a smaller one for date night, etc.
I have nothing but great things to say about Le Boy.
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I don’t think you can go wrong with any of these three. My least favorite of the 3 would be the M/L because it holds less. But, that’s really after trying to find a reason to like one less and picking nits. You wouldn’t be able to get my M/L out of my cold dead clutches because it works so well in my wardrobe.
My advice would be to go to a Chanel boutique and try on all three. Put your things in the bags. Try them shoulder and crossbody if they offer the option. And, try them in any color you think you may love. Black isn’t the only color. I own dark grey, pearl grey, gold, red, ivory, beige and black Chanels. And I’d love ones in other colors too like pink or blue.
When you fall in love, that’s the bag for you!
Share pics of what you buy.
