I haven't used any Visiontek cards so not sure on those, but if they're 280X then the settings are likely all the same except for finding that card's sweetspot on the gpu speed.

You should be able to get close to 1/2 the hashrate (or a couple % less) than you get for regular script coins. That's normal for VTC.

I've just used the vertminer (custom cgminer from the VCT homepage) so far. Seems to works good, but you have to take the default config file out of it's folder if you want to use a batch file for launch and config (otherwise the prog uses the parameters in the config file instead of what you put in your .bat). And in the .bat file, the command line needs to start as "vertminer.exe --script-vert........". If you leave out the -vert it'll drive you nuts wondering why it won't work    (This is compared to regular cgminer command line starting as "cgminer.exe --script ........")