That depends. I assume by "run your own DNS" you mean to setup a local DNS server that performs its own root lookups. If that is in fact what you meant - I don't see the benefit unless your ISP has a really messed-up DNS server. Typically (again, I'm assuming - you know what that means) the closest Internet DNS servers outside of your LAN are going to be your ISP's - and unless you have real bonehead for an ISP, those servers are reasonably well configured for the root servers and caching operation. So contacting the Internet root servers directly means increased communications distance - as well as increased load for servers that aren't intended to be contacted by umpteen million small businesses.Now, in your workstation's resolv.conf, you list 192.168.0.1, along with your service provider's primary/secondary servers.you do NOT need to use your isp server .. if you run your own dns
Since I haven't tried it yet myself I can't offer much else - though I'd like to hear about comparisons between a well-run ISP's DNS servers and using your own gateway server to contact the root servers directly.
isp is OUT of the picture and is not required if dns is properly setup for your domain
Again, in my very unauthoritative opinion - it depends. -- Daniel