I use my MiSTer on a Samsung Full HD LCD TV via HDMI. Vsync_adjust=1 works fine in all 60 Hz cores and scrolling is butter smooth with low lag, but on all cores where I use 50Hz PAL (e.g. Amiga, C64) it doesn't sync, so I had either use vsync_adjust=2 which results in stuttering in fast scrolling games (e.g. Uridium) or try to run the games in NTSC mode which is not compatible with many PAL games.
I just found out, that vsync_adjust=1 syncs, when I run the MiSTer in 1280x720@60Hz. The downside it, that it is not the native resolution of the display, which dimishes the image quality, but to me that's much better then stuttering scrolling.
If you have problems getting vsync_adjust=1 to work properly on your LCD TV try it at a lower resolution, this might help.
You can set the resolution per core, so that you don't have to run all cores in the "wrong" resolution.