Had experience with SendinBlue. Actually, everything is great except that moment when you have to add the list of recipients. Cause it is after the design of your email, which is not useful. Also, I faced one problem and Support Team helped me within some hours, thanks!
Dear Mihail,
Thank you a lot for leaving feedback. We will make you happy many times in the future.
Jennie M. Your manager at Masterra.com.