I decided for myself the trouble was worth it. In my case the decision was easy: either pay and have less hassle, or have "trouble" and pay less. Since I don't like to pay for stuff I can get for free, I decided to not pay. Likewise, I'd be unwilling to pay for software, operating systems or email services.
And I installed cacert's root certificate into my webbrowser, so I don't get as many warnings.
cacert's competitors are fighting very hard to keep cacert's root certificate excluded from software (i.e. firefox' built-in security token): their business relies on this.
I don't trust verisign more because they charge more; given their history with what they did to DNS, I am inclined to trust them less. Lucky for us all, there are many other CAs out there, many of which have their root certificates built into software packages, so one can get an easy to use certificate without paying too much.
I'd suggest dropping one certificate if having two is a problem.