Well I have the Dell monitor and it's really nice - still that would be the only thing I would buy from Dell... monitors..
If you go the normal WinPC way build youre own.. You can def. shave off a little money and get a better piece of machinery and not suddenly discover that some part cant be changed due to some odd Dell specs..
But still you really need to think about the change... WinPC or Mac
The monitor size is def. huge compared to a 19" or similar, but believe me 24" is easy used, and I would not hesitate to buy the Dell 30" if I had the money right now..