1080p TV is nothing like using a 1080p computer display.
1080p may be 1080p, but the size of the display is whats going to make using a TV problematic. Folks who use TV's as computer displays always have to place them much farther from their sitting position, whereas computer monitors can be used within your desk area (this varies on screen size and resolution: DPI). Display tech is also very important, as mentioned above. NO LCD/LED TV is going to match a good IPS display.
Anyways, a commenter above made a great recommendation with the Dell Ultrasharp. You can actually find their 23" around $220.00. no tax + FS. I'd get two of those for a Mac Pro. Granted, the best thing would be a 1440p or 1600p monitor, but those are pretty expensive. Good Luck!