I used the Dutch one for internal Irish VFR flight plans before. It always caused problems, with Dublin complaining they didn't have a copy of my flight plan, and I had to wait while they contacted Shannon to get a copy.
Shannon always had the details. I spoke to AIS in Shannon about it, and they were able to confirm that the flight plans were entered into the system, but after an explination of the problem they said "Humm.......it's addressed very strangely". Gave up using it.
Homebriefing....works great....had a couple of flight plans go missing at Dublin and only 1 ever go missing elsewhere. I don't know what it was about Dublin as they never lose flight plans filed with AIS in Shannon, but they would lose the odd one filed with Homebriefing.
dp