Who's a champ you used to dislike but now really enjoy?
Title
For example, I tried
when I first started playing the game when he was on free week and I just couldn't do anything with him. He seemed so awkward and weird compared to normal champs. A couple months ago he was on free week again so I thought I'd give him another shot and holy crap is he fun! He's definitely not overpowered but his kit has some real strengths and weaknesses that can allow me to get ahead if I play well or fall behind if I play poorly. I really feel like I'm in control of my own destiny with him and if I lose lane I have no one to blame but myself. His heat mechanic is also really unique.
I was wondering if anyone else had this kind of experience with another champion. You tried them on a free week and you just didn't like them and then you gave them a second chance later on and found out you really enjoyed the champ.

and 
He's actually quite fun.....I really do hate myself though because I know what the enemy midlaner is going through when I'm doing well in lane.
I sucked at them all and hated how others could get freelo off them now they are my mains. Rammus support main 90%+ win rate
Edit: now 87.5% ;=;
After her Rework i decided to check her out. Old Tristana was my most hated Champ, now shes my second most favorite
- used to think he's shit, but then i had so much fun i didn't care.