I bought the lifetime deal here on AppSumo one year ago I believe and I have zero regrets. Subscribr has saved me hours of work and a lot of friction in my video scripting process — everything flows so much more smoothly now.
What really impressed me is how fast the team ships: since I purchased, they've released a ton of new features in a very short time. All of them are included in the lifetime deal (with some limitation but I don' even use all the credits I have) That's rare and worth mentioning.
There are also plenty of tutorials to help you get the most out of it. The team is great and they really care and help you to use their product.