I concur with hong. We went back and forth on this one and ordered the sunroof at the last minute, glad I did as here are my top reasons why...

1. It's huge and you can see the "little white puffy clouds" [think the Orb], jet trails, and things in flight or watch the planet rotate when you are orb'ed out.
2. You actually receive sunlight here in Vermont when it's not covered up by little white puffy clouds.
3. You will be able to drive and motor better, because you can hear your engine and supercharger more effectively.
4. You'll get in touch with the wind (yes it's noisy, but that's what your volume control **** is for... and #1-3 overrule the noise anyway).
5. It will enable you to raise your winning checkered flag higher on the victory lap (as opposed to only out the window).
6. When you absolutely need to shop at Home Depot you can! Go ahead and order the 10 ft section of drain pipe you've always wanted and think nothing of it.
7. Ornithologists LOVE sunroofs. When clipping along the interstate you have a better chance to educate your sons & daughters about Red Tail Hawks, Osprey and the Perigrine Falcon, Vermont's state bird. Heck, the MINI is the only car able to keep up with the Perigrine...
8. Added spoiler effect when kicked up, adds at least 3-4 mph.
9. Less paint to wax...
10. Save electricity and blow dry your hair!

 

Everything what everyone else has said supporting the sunroof and to add to the pictures, my favorite picture of my MINI:



(I have posted this picture on here too many times!)

Also if you have the sunroof in the winter, you can park in the sun and the car is warmer than usual when you get back.

 

I have the sunroof and love it. That being said, I wish they made an opaque shade for it that you can leave in and open or close it as needed but still also be able to use the mesh shade