I checked latency with DPCLAT.  It looked like the average was on the order of 100 microseconds.  After letting it run for a few minutes the worst reading was a little less than 500 microseconds which was still in the "green" zone on the plot.
 
I have also continued to have good luck with running lower latencies under X3e.  6-8 msecs ASIO buffer looks to not be a problem with the project I've been working with.  I can drop the buffer down to 2 msec and its still tolerable.  I still notice clicks and pops from time to time, but that may be due to the softsynths I'm using in this particular project.  I've got a couple of instances of Poly-Ana with oversampling set to 16x and this synth was at one time known as a CPU hog.  Subjectively, the outboard synth grooves well with the VSTi's.  Sometimes, I feel like I can hear a slight difference between the bounced track and the live monitored track for the outboard synth but it's much more subtle to the point that I'm not sure if it's just the placebo effect.
 
Anyway, thanks for the help everyone.  I think everything is working satisfactorily now.  Time to stop testing and get back to making music.
Dan