Hi,
Yes, I'm doing everything on one Mac so far, although my usual setup involves 2 slave Macs as well. I just wanted to see how far I could go on my main 8-core Mac. So at the moment, Logic has 14 VE Pro plugins connected to:
(1) 64-bit server running (12) multitimbral instances of Kontakt 4.1 and (8) instances of VIenna instruments (200 instruments total)
(1) 32-bit server, which is running (16) instances of East West PLAY.
Logic is running at a buffer size of 128, all VE Pro plugins are set at 2 buffers, and all are decoupled - otherwise Logic really slows down on certain editing operations & save times. Decoupling is no big deal for me - all I have to do is save a metaframe of the whole project. As for Kontakt, as long as you're on 4.1 you can disable KMS (Kontakt's memory server) and run it in the 64-bit VE Pro server. That will give you access to all your RAM. For earlier versions you will certainly want to enable KMS.
It's still a work in progress for me; the next step is to try and spread the load a bit across my slave computers and see how that works. Except for a few bugs with VE Pro, it's working very well, at least conceptually. If I can get it working with such a large setup & take advantage of offline bouncing, I'll be a VERY happy guy.
The main bug I'm noticing is that offline bounces in Logic aren't properly compensated for VE Pro's buffer latency. If I set buffers to 'none' it's fine, but it's a pain to have to do that every time I want to bounce something - especially across 14 instances of the plugin! Hopefully that will be fixed ASAP. I started another thread about that here - see that for more details.
Hope this helps a little!
Jim