Very good and very underatted. I know it sounds crazy, but I actually think his redemption is more natural than Vader's. No matter how many bad things he did, his conscience always got to him. After losing the 3 people who he believed saw good in him (Rey, Solo and Leia), he saw that he wasn't getting anywhere, made worse by the fact that despite being in power, he was really just under Palpatine's thumb.