Macbook Air w/ 13", i5, 8GB - how powerful is it?

I'm on the verge of buying an Air with said specs, but I need to know what to expect in terms of performance.

Do you guys think the following scenario is possible:

*15+ tabs open in chrome and

*a second browser open with a bunch of tabs open and

*a bunch of flash videos loading and one playing and

*running Xcode and debugging e.g. with the iPhone emulator and

*running a couple of other programms

*all that while having a 1080p external monitor pluged in (the flash video should be viewable on the external monitor with no stuttering at all)

I'm a student and 1300€ is a lot of money to me (actually will be the most expensive thing I ever bought). I would dislike it if the macbook would slow down all the time :/

Please help me with your honest opinion.