What does the company do well? Contactually is an amazing take on the CRM. It does a lot of what normal CRMs do but the added element of tracking frequency of contact, and making it easy to make sure you stay in touch with people on regular cadences, is so incredible. It helps you avoid those "oh I should reach out to XYZ" moments that you have far too late.
What does the company not do well? The pricing is a bit high if you are focussed mainly on its contact cadence features, and aren't making use of templates/programs/pipelines/etc. Those are powerful features for sure, but if you're using it mainly as a personal CRM/reminder tool, you likely won't use them, and will pay a lot out of pocket for features you don't need.
What do you wish you had known about the company before using? To really get the most out of it, you need to be able to devote at least 30 minutes a day, and a lot more at the start (to bucket/group your contacts, which is pretty much required to get the most benefit from the product). If you don't make that commitment, contact reminders start to pile up and you can start to get bogged down.