A little big dilema, DLGuard or autoresponder?

Hi All,
A little feedback would be very helpful here. It's a question I see insinuated here by accident many times but so far I've not seen it discussed directly.
I'm laying the foundation stones for an online business I have hopes for, hopes that really justify my doing it right now and not taking shortcuts or making mistakes.

Keeping track of customers is going to be very important. I just had run in an autoresponder service and now admit to being extremely nervous about trusting the financial corner stone of it all to a service that can wipe lists, cancel mailout operations midstream (that was my latest problem, I was re filtering a year old list according to their directions to take out non users. They stopped it mid stream 'in case it might generate opt outs and spam complaints'-this despite my record with them of in three years I have never had a single spam complaint and an opt-out rate of less than 5%. I'm still fuming and can't decide to just cancel my membership with them or go over the office pucks head and complain about someone creating work for themselves.)

So, I have no experience yet with DLGuard, but it seems that if I have 100% control over my own customer lists then I'm removing a risk, whether big or small, that could have a massive financial downside. Imagine if even just one time, the list of my paying customers just vanished into the ether with no come back I could draw on, it makes me shudder.

What do you all do? If you have a 6 figure income, do you risk it on your autoresponder service having a coniption, ... is there a better way?

Does DLGuard have its own inbuilt autoresponder and list manager that would handle a 6 figure long list?

Many thanks, BR88