I like that it works with both Gmail as well Outlook users, but for different reasons! The software has really helped us manage our campaigns from start-to-finish which makes running them easier than ever before (that's not an exaggeration). It also provides great insights into who opens your emails so you can target future communications better if needed via segmentation tools or in other ways through A/B testing etc... This service allows me send out personalized newsletters at no extra cost compared to sending mass ones - we've seen significant results across all of my customer segments thus far since starting this program 2 years ago!! We're trying new things every month now without having too many issues managing each campaign individually vs one central solution where everything gets synced up seamlessly together :) Great product overall. They are constantly adding more features making what they offer even greater by providing additional value added.