The current Asha 311 and its interpretation of Swipe-UI is very disappointing. it has performance issues, low frame-rate, the small screen also doesn't help.
What made the Swipe-UI work on the N9 was a lot of the hardware: high frame-rate because of hardware GPU acceleration and a relatively large screen. Also the lack of buttons emphasized the swipe-usage and the curved glass made swiping feel more smooth.

If they re-introduce the UI on new phones, even if they are budget phones, the UI should work at least as well as on the N9, otherwise it will remain a disappointment for me.