Z-wave suddenly a hot mess on the OmniPro II


I know from painful experience the "suddenly" word is often anything but (i.e., usually given enough thought one can trace something that DID change) but I find myself "suddenly" having awful problems with z-wave and I'm at wits end, and looking for advice please.
Basically, a couple weeks ago the OPII z-wave performance became very erratic. No code changes or anything new or different - just that z-wave no longer works reliably. It went from 99% accurate to maybe 75% accurate: events and inputs trigger just fine from what I can see in the "Status/Control" pane of PCAccess - flags and timers get set, inputs are received, etc. but z-wave is just not getting out.
When I do a refresh download ("Write to Controller...") of the whole shebang, things work again for a day or two... and then z-wave fails again.
Interestingly enough, when I send z-wave commands directly from the Vizia RF+ stick using the Leviton Vizia RF + Installer Tool utility, everything is received and works fine.
I have had lousy experience with the Leviton Vizia RF+ serial interface module and I've replaced this critical component three times already... but at $135 a pop, plus a few hours relearning all of my nodes (I have 61 z-wave devices), this gets old. All of my z-wave devices are the Leviton VRM10/VRI06 - in other words a few years old and do not have NWI or the more "reliable" feature-set of the current z-wave code. But just as I don't want to keep replacing the Vizia RF+ serial module, I also don't want to run around replacing every dimmer in the house.
So far, because commands wok fine from the Leviton RF stick, that I keep replacing RF+ serial interface modules, and that things "work" fine for a day or two when I do a refresh download of the OPII configuration from PCA, I'm suspecting that something is going bad with the OPII serial port perhaps?  Just an uninformed hunch.
I've been looking at the Homeseer Z-NET Remote Z-Wave Interface and wondering if this is more reliable than the Leviton Vizia RF+ serial interface??
I do have Homeseer running behind the OPII, but to-date I am using it only for things the OPII cannot do natively, such as play .wav files on events, and manage e-mail actions. I'm thinking (especially since Leviton bailed on HAI) that I start to move all of my event code to Homeseer and just use the OPII as an I/O board and touchscreen controller.
If anyone has thoughts based on what I've shared, I would be very grateful.


Here long time ago used the Homeseer RPi ZWave dot me module to upload the ZWave data to the Leviton ZRCOP serial device via the ZWave radio. 
I have not had issues but ZWave is not primary here.  IE: UPB, X10 and Zigbee are also used.
Have you tried hooking up the VRCOP serial interface to Homeseer?

BTW here still using original HAI VRCOP.


Thank you Pete.
The last time I used the Vizia RF+ serial interface (VRCOP) with Homeseer was probably 15+ years ago, and if I recall it involved a USB to RS232 adapter, then another adapter to DB9... I'm not keen to setup something so kludge-y again so I may just buy the Homeseer Z-net and see if I can get better reliability with Homeseer managing the Z-wave interface.
Do you happen to know (and no worries if not - I can just test and see) if I can have the VRCOP hanging off the OmniProII AND another Z-wave interface (the Homeseer Z-net) running in parallel? In other words, I'm wondering if I can setup the Homeseer Z-net and have that "create" its own node map of the Z-wave ecosystem, while also leaving the Leviton interface - with ITS own node map of the same Z-wave ecosystem - in place??
I do understand that network traffic is network traffic and this may likely create double the amount of network traffic - at least insomuch as I would have the OmniProII code running with overlapping code (i.e. for identical events) running within Homeseer. I'm thinking of just letting the two systems duke it out and whoever gets the command to the respective Z-wave node first "wins".
I no longer trust the reliability of anything that does not have a hard copper wire running to it! This radio stuff is for the birds...