Why do Google DNS servers work better than Plusnet's?

[#1]

I recently bought a Netgear DGN1000 wireless router. It worked fine except that on first access to any given domain it would very often throw up an error like "Firefox can't find the server at www...... (whatever it is)". This also happened with IE and when downloading mail from the mail server. The second and subsequent accesses would work.
After several iterations of trying different things with Netgear technical support the solution that worked was to change the DNS server addresses to 8.8.8.8 and 8.8.4.4. They had previously been set to Plusnet's servers as recommended in the "setting up an internet connection" instructions. The new addresses, the ones that work, are I believe a public DNS service provided by Google.
So my question is - why would the DNS servers at Google be more reliable than Plusnet's?
By the way, using my old ADSL modem I didn't get this error.

[#2]

I'm not sure it's a case of Google's DNS workng better then Plus Net's, possibly more a case of the Netgear router not working correctly when set to automatically pick up the DNS servers (a known issue).  Have you tried inputting the fixed addresses for Plus Net DNS?
Having said that, Google have probably invested a fair bit in ensuring that their DNS service provides good performance (otherwise they'd probably not even offer the service).
Have you tried http://code.google.com/p/namebench/ if you want to find your best DNS response time?

[#3]

Quote from: walker23

I'm not sure it's a case of Google's DNS workng better then Plus Net's, possibly more a case of the Netgear router not working correctly when set to automatically pick up the DNS servers (a known issue).  Have you tried inputting the fixed addresses for Plus Net DNS?

I had it set to the fixed DNS addresses for Plusnet from the start.
And it didn't seem to be a speed issue. When I got the error it would pop up immediately on trying to access a web page. Then when I clicked click Try Again it would find the web page and load it just fine, every time. The error would happen again when I went to a web page at a different domain.

[#4]

I have the same problem with my Netgear FG834G v4 with Google server hard coded as the primary
Update
I have just tried hard coding the DNS servers Google as primary Plusnet as secondary into Windows and first impressions are that it is much faster without the "looking up" delay showing at the bottom of the browser window
Will report back after 24 hours or sooner if the problem reappears

[#5]

Hard coding the DNS servers into Windows 7 seems to have fixed the problem so the cause must either be in the router response times or the Windows network connection
EDIT
Just had one more failure - retry found it

[#6]

@Oldjim, having done extensive DNS testing myself, while Google DNS is invariably faster and more reliable than responses from the Plusnet DNSes, the Google DNSes do appear to drop maybe a few percent of requests.
I find that the OpenDNS servers are marginally faster than Google, and respond 100% of the time.
Recently I have found the Norton-DNS is also usually faster and more reliable than Google.

[#7]

I'm currently using 194.73.82.242 as my primary DNS and it's quite fast.

[#8]

Just had one more failure so have switched my primary to Open DNS