Should You Host Your Own Nameservers?

I'd recommend PowerDNS highly, if you just want a no-frills recursing DNS server to enable Internet usage, pdns-recursor requires close to zero configuration to be used on a local network. I use it on our FreeBSD server on the office, and basically, I just installed it, added the server's IP address to /usr/local/etc/pdns/recursor.conf and started the service.

If you want to provide your own DNS information, PowerDNS has some very powerful features, mainly in its ability to use a relational database as backend, which makes it a lot easier to make some sort of web interface or configuration system, and also makes it a lot easier to do replication, since you can just use the database server's replication system instead of AXFR or similar things.

Unless I'm misunderstanding the question, I do this regularly with BIND, and it seems to be fine as long as each zone is absolutely identical.

On my primary nameserver, I have named.conf entries that point to the generic zonefile, eg

zone "example.com" {
        type master;
        file "primary/example.GENERIC";
};

zone "example.co.uk" {
        type master;
        file "primary/example.GENERIC";
};

and then a zonefile primary/example.GENERIC which says, eg

;; Start of Authority
@       IN      SOA     ns.teaparty.net. dns.gatekeeper.ltd.uk. (
                        2004091201      ; serial number YYYYMMDDNN
                        28800           ; refresh  8 hours
                        7200            ; retry    2 hours
                        864000          ; expire  10 days
                        3600 )          ; min ttl  1 day
;;
;;      Name Servers
                IN      NS      ns.teaparty.net.
                IN      NS      ns2.teaparty.net.

And I'm not aware of any problems with these zones at all. I'm open to being told that I've misunderstood the question, or that my domains in fact don't work, but until then I think it works for me.

Note that you cannot pull the same trick on the secondary; each zone will require a different file to be stored in. But since the contents of that file will be populated and kept up-to-date by zone xfers from the primary, this isn't a huge deal.