Fastest Newlsetter Mailer?

I would like recommendations from any of you about newsletter emailers you may have used and had success with.

I currently send out a newsletter to a list of 4 million subscribers at a rate of between 5k and 10K per hour using ListMail Pro. It appears that the developer that developed this has disappeared, which is one reason to change software, but also this delivery rate is too slow.

I’d like to get the speed up to 100K per hour. I have 2 managed private servers which I’d like to run linux on and would prefer to use an open source solution although purchasing one is an option too.

Is it unrealistic to expect a php solution would be able to do this? Assuming the RAM, CPU and bandwidth are highly availabledo you know of a solution that can deliver this kind of speed?

So far I have liked the features of openEMM but I’m not sure it can perform at this level.

Any guidance is appreciated.

Probably a dumb question, but have you considered options like CampaignMonitor? They have lots of great functionality and take a lot of the stress out of sending your own stuff.

Out of interest, how do you ensure that your server doesn’t get blocked when sending out that much mail? Maybe I have just been overly spooked, but I keep hearing about ISPs that get very suspicious about large mailouts.

I’m currently sending at 5-10K per hour. We have a long standing, legitimate newsletter with opt-in/opt-out that we mail. Haven’t had any problems yet but need to cut down the time. At 100K an hour it would still take 40 hours to get through our list.

A third party manager would be a last resort due to the cost of those services but that may be an option. .01 per recipient…4M recipients is $40K per mailing. Our headache just isn’t that big.

Has anyone used openEMM at this level? Majordomo?

I’m wondering if the mailing could be done by one software and the management of the list performed by another?