I traded my 30d for a 1D and I have enjoyed it so far. The largest I print is 8x10 and the 1D can print 8x10's perfectly. The only downside I see for being half the megapixels is that you cannot really crop. But that doesn't really matter if you compose your shot right.
The only two things you might hate about the 1D is that you will fall in love with the 1D series and you will hate the battery life.

Did you "refresh" your battery? How many shots do you get out of your 1D?
Compared to the MK3, the battery life is shorter but acceptable.





