They are also one of the hosting companies that I use with my clients and they're currently my web host. I've also been very happy.
Regarding outages and NetVirtue I'm only aware of them having one major problem that lasted a few days and it only affected some of their customers on one of their servers.
However they were able to communicate the issue directly and on their status page with their customers and were active on whirlpool as they have multiple representatives.
And after they were back online they performed a incident investigation which they made their findings public. But this incident was probably more than three years ago.
VentraIP, Also handle incidents pretty much the same as NetVirtue and I'm only aware of them having one or two incidents Nothing recently in the last two years.
NetVirtue, Run their own hosting infrastructure, and resell the domain names through Synergy Wholesale which is VentraIP's Wholesale Division.
VentraIP, run their own infrastructure as well. All their domain name registration is done these days are through their wholesale division synergy wholesale and are accredited directly for every single domain name extension they sell.
So my normal recommendation is at the moment on Whirlpool VentraIP for domain name registration. they are pretty much the best Australian provider when it comes to domain names.
When it comes to hosting I can highly recommend these and have use them for clients and myself these providers are all great as well and have good reputation on whirlpool.
Zuver (VentraIP's budget brand.)
Panthur (it has one of the best support levels and reputation on whirlpool I would also agree they're excellent)
If you have a large portfolio of domain names OR Want to resell domain names I can highly recommend Synergy Wholesale. Most of my domain names except for a small handful a in my synergy wholesale account.