hi Sassy - I have two keepall xs because I really liked the sunset monogram and I’m a sucker for mono eclipse and mono eclipse reverse. When the speedy 20 came, I loved it too! The bags are about the same length, the keepall xs isn’t as tall. But I can carry all my essentials in the xs - CCH, MPA, and a few other things. I also hook a cles to the outside for my AirPod pros. Love that option as it frees up space in my bag. The speedy 20 will hold more and the speedy handles can be hand held - the keepall is :finger held: with the handles, but not an issue as I wear it crossbody.
As for being different enough, I think they are (but likely that‘s a rationalization because I wanted each of those bags!

). I do find the keepall lays closer to my body on crossbody wear. I travelled with the sunset keepall and it was perfect for crossbody and safety, and was big enough for passport, and all essentials. it was also a great size to then stow in my carryon on the plane. It truly was a carefree bag that I didn’t baby at all. Especially with no vachetta on either keepall. HTH