Neat website, can get games for cheaper than on steam, was very easy to use, there are even instructions on how to do everything properly so you'd have to try really hard to not receive your games.
Unity is great simply because it is popular and has a large community of teachers and learners who can help you solve various coding related problems. Recently a lot of great and successful games have been made with Unity so learning it might even help out when looking for jobs. It has also evolved quite a bit recently and is definitely on par with other engines.