Have Samsung LC34H890WJUXES staying on top of it without any issues, have used both a fixing bracket and a second fixing option where you drill a hole in tabletop.
Probably. The key is the monitor's weight. I managed to put LG 34UB67-B on it with no problems at all. Philips Brilliance BDM4037UW/00 is much too heavy but I've built a support structure for it an now I have a nice stacked setup.