FLUD and Slide Reader
After several days researching I'm leaning towards FLUD or Slide Reader.
I promised myself I wouldn't do this but I did... I bought both!
FLUD was the first one because it was cheaper. the interface looks good but usability is a little complicated.
It lags, no smooth transitions between rows and columns scrolling. It stores the last 12 articles of each feed and that's it. You can't configure for how long old feeds will stay active, it's always the last 12 (if there's a way to do it I didn't figure out).
It comes with some popular feeds already loaded and there's a list of preconfigured feeds, you just have to check the ones you want, if you want.
All the feeds you add automatically turns into a row of 12 feeds, and you can categorize it using one of the predetermined categories in the app but no further customization. I think it's OK for the casual reader but if you want a little more control you can't have it.
You can't read the feeds in fullscreen, there's always a space on the left or bottom (depends on iPad orientation) for the feed rows, a waste of space. You can pinch to zoom though.
No Instapaper integration.
In sum, very disappointing.
Slide Reader: What a difference!!! First of all, it's fast! Smooth navigation, no lags.
The start screen has no feeds and have instructions for initial config.
Lots of options! You can configure for how long old feeds will stay on screen, or when the read feeds will be deleted and a lot more.
You create your own categories to organize feeds and all the feeds that are in the same category shows in one row in chronological order. One feed can be set to different categories at the same time.
Instapaper integration and others like Google Reader (I don't use this), Read it Later, Facebook, Twitter, etc.
Themes. You have 3 options in app and can download more online (don't know if it's free).
Profiles. If more than one person is using the same iPad you can create different profiles for them, or if you want to organize more you can use it for distinct subjects for example.
I'm very happy with Slide Reader so far, five dollars well spent.