How can I use Aweber for Forex marketing?

Is it risky for a forex company to use Aweber for email marketing? I’ve heard stories of entrepreneurs having their accounts shut down and I don’t want to risk my company’s deliverability. We plan to use mainly promotional content to increase sales, but also provide informative and valuable content. We have a large amount of leads to import (over 50k). Is there any potential problem with that? Is it true that most forex companies use MailChimp? What do you recommend? Thank you for your help.