MacBook Air as a main computer?

I bought a Dell Windows 8 laptop in January and without boring you with all its faults, I am completely unsatisfied with it. So I'm now considering buying the 13' MacBook Air to replace it. My question is would it suffice as a primary computer or do you really use it when you are out and about or as a secondary machine?

My computing activities include multi-tabbed browsing (i do a fair bit of research so I have plenty of tabs open at once), a bit of programming and SQL work, word processing/spreadsheets and for entertainment, I watch videos and listen to music.

On the subject of portability, it's not essential that my computer be very portable, but I do like the idea of sitting down at my local cafe and getting some work done. I'm also a consultant, so I travel, but I use a company PC that I can't install my own software on, so it would be nice to take the MBA around with me.

So, in your experience, would the MacBook Air perform well as my one and only computer?