You could not be any more wrong on this with that statement. The ISP is not the issue and the hardware is not the issue.
If you are to build a recursive DNS server and have it do recursive queries on the internet completely bypassing your Router and ISP's DNS setup - you are still vulnerable.
If you're familiar with Dig - you can use the commands found on this great article: http://www.cyberciti.biz/faq/dns-cache-poisoning-test/
You could not be any more wrong on this with that statement. The ISP is not the issue and the hardware is not the issue. If you are to build a recursive DNS server and have it do recursive queries on the internet completely bypassing your Router and ISP's DNS setup - you are still vulnerable.