Also, in list of VST fx, there are two versions of each UAD plugin.  One appears to be mono and one stereo.  It was not like this in X2 and appeared like this in X3 prior to me updating UAD, so it appears to be X3-related.  Anyone experience this?  Do we now have to have two versions of each, like Waves?

Biggest reason to use the mono (m) versions is reduced DSP usage per plug-in instance. Using the mono versions on mono tracks (instead of the standard versions), will save DSP. Depending on the plug-in it can save up to 40% DSP usage per instance (ala FATSO w/ tranny enabled). If you do not use any mono tacks or don't mind wasting valuable finite DSP resources then stay with the standard versions and just delete the UAD mono plug-in folder. Then just re-run the X3 plug-in scanner. You may want to "reset all" first to clear out the mono entries first. Typically,  the mono VST versions were optional at install. I think they are installed automatically now. Most of my tracks are mono (vocal, bass guitar, snare, kick, etc...) and I use a lot of mono VST UAD plug-ins (80%+ of UAD plug-ins are mono instances). I typically, get an extra 25% DSP (on average) on my QUAD by using the mono versions instead of the standard ones.
 
SONAR UAD users should be happy, as UA has brought back the mono VST versions with the arrival of v7.3. UA had stopped providing mono versions of new plug-in releases post v6.3.1. Fortunately, after some persuasion as to the benefits the mono versions provide to not only SONAR, but various other DAW apps (REAPER, Samplitude, Sony apps, etc.), UA re-instituted the mono VST versions for all new UAD plug-ins (about 20 of them) released since v6.3.1. Now I can use a mono VST version of the Vintage Amp Room and only use 16.1% DSP per instance, instead of 30.5% using the the standard version on my mono guitar track. Woohoo!
 
Cheers,
 
Billy Buck

Great, thanks, that makes a lot of sense.  Still a mystery why they just showed up in X3, though!

Treefight
Great, thanks, that makes a lot of sense.  Still a mystery why they just showed up in X3, though!

 
The mono VST versions were optional before and you had to manual select them to be installed. I think now they are automatically installed.
 

Using the plugin manager I made a UAD Stereo folder and a UAD Mono folder in my plugin drop down list , That really made it easy.