I found it to be awful. It's so slow. I presume this is an artefact of using it from Europe, and the developers not taking latency into account.
I'm willing to overlook the bugs such as the same item appearing more than once in a feed (it's quite new), but the incredible slowness of it make it unusable for me.
For example, I loaded it before writing this comment, and as of this point, it still hasn't finished loading. I just get a spinny box and 'Loading...'
I also know from experience that if you click on something else, such as a folder, it won't override what it's currently loading, so the state of the UI will get out of sync.
You also can't read a list of items, you have to read one by one, incurring yet another AJAXy-load which doesn't necessarily ever respond, thus leaving in you in Loading... limbo.
That's interesting. I'm using it from Australia and it seems acceptably fast for me. I don't have a huge number of feeds, maybe this makes the difference.
Did you contact the developer? She seems quite eager to help.
Those are significant items that need to be worked on, but the main thing Yoleo does for me is feel good using it like Google Reader felt good several years ago. I haven't come across an RSS reader in awhile that didn't make reading feel like work.
I wanted to love it, but it takes forever to load on my iPhone 5. The base page loads fast, but the Ajax call to fetch articles just spins forever. (I live in Omaha, Nebraska, fwiw)