I have 2 Samsung Pebbles but the OC 24" gets my vote.
The price is similar but the 24" has a higher resolution which will give you much more desktop space over the Pebble. The 24" also has a better panel with regards to viewing angles, backlight bleed and possibly colour reproduction. The Samsung has a ever so slight edge in gaming.
I went for the Pebbles personally because I wanted a tri-monitor setup and I just don't have the space for a 24", especially one as bulky as the OC 24". If I only needed one monitor on my desk, the choice would have been the OC 24".