Regarding the auto-response, I was very aware of the issue, which is why
when I signed up for the list, I requested a daily batch
I tried an auto-responder for a few months and it caused way more
complaints from people than compliments.
Actually it will be a configurable option in AccuSpam, because we don't
absolutely need it, but it does aid detection of inexistent address over
non-response methods we will offer as an option.
But realize the auto-response (it is not a challenge) does not get sent to you
if you are on my whitelist, so the problem is really only with mailing lists.
You'd may or may not know that 95+% of email users do not use mailing lists.
Actually I don't think I ever
received a compliment regarding an auto-responder. I recommend you
disable it altogether.
I've never received a complaint, except from mailing lists. Whitelisting all
mailing lists is one way to handle the issue as I stated.
I haven't tried Pair, but usually pull their mirrors for stuff like
cpan. They seem to have a reliable network.
However, I do run three servers on Rackspace, and don't have any
complaints. One thing about Rackspace is that in addition to US based
servers they also have Non-US based servers which makes sense in certain
situations.
Yes I also like Rackspace also for various reasons such as that, but the main
problem was their IP C class keep getting into RBLs that they could not get off
of readily. And Pair offers a more stable (single platform well tested) option
if you do not need a lot of root access tweaking.