Ask HN: Who are you using to manage your email campaings?

I'm looking for a company to send and manage email campaigns for a client. It's been tough to research because anytime you search for anything related to email marketing you are instantly knee deep in junk. I've looked into companies like MailChimp, Contactology, and Campaign Monitor and I was wondering if people had any other suggestions? There are a couple requirements that even some of the companies I just listed didn't meet. We need to be able to send transactional emails and have them tracked and included in reports. A web accessible API is a must but it seems almost every company has that these days. Pricing isn't as much of a factor as functionality is but obviously it needs to be considered. The best option I've found so far is Contactology because it lets me create automated triggers like 'send this email when user is added to list' type thing. That's what we are looking to do, more one at a time emails then massive campaigns. Any help is most appreciated.