I have it deployed in two locations right now.
We use it internally in two instances, one for each of our routers at each end of our network. If router A fails, traffic destined to that gateway goes to router B. If router B fails, traffic to router A, etc. It works as expected and I have not encountered any bugs or stability issues.
I'm running 6.7 currently. Our in-house setup is on x86 and the setup I have deployed for a client is on the RB2011 platform.
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