Sam, we're going to purchase a license, but we're uncertain which tier is applicable. Again, our use case is to send a personalized landing page to every reply we get. We're shutting off the open rate feature in the email sender platform to avoid spam filters, so this means we have to rely on the actual replys we receive. My thought is, having a personalized landing page could capture attention to those contacts who passed the first time, perhaps we add a link in the third sequence, or wait anothe rmonth with a follow up email and include it then. We are sending out 7K-8K new contact 'data enriched' emails per month. In this case, should we consider going with tier 4 or 5 due to volume?