What does the company do well? OptinMonster is great for capturing leads or even driving conversions. Their software is really easy to integrate with a simple tag in Google Tag Manager, or by using the built-in WordPress plugin. One of my favorite things is all of the campaign display options. For example, you can have your pop-up show after 'x' number of seconds, after scrolling to a certain part of the page, on exit-intent for browse abandonment, and a ton more.
What does the company not do well? When we were first trying to get everything set up, there was a small learning curve where my campaigns were not showing up, but I was able to get that problem solved pretty easily. My recommendation would be for a more technical onboarding experience (however they may have fixed this by now -- we have been a customer for over a year).
What about the company do you wish you had known before purchasing? I wish I had known about the WordPress integration option before I added the tag through Google Tag Manager. It's much easier in there. Also, you should know that this software plays nice with MailChimp and other CRM platforms, so you can send your leads directly into an automation campaign.