You're hard-pressed to find anyone who will speak for Skarner in any role, I think. It's even more uncommon to find really good Skarner players.
I'll just say that Skarner is my favorite of all the champions even through all the buffs, nerfs, and reworks. I pick him for jungle 100% of my time on SR and I always win jungle with him and make meaningful successful ganks for which my team thanks me. We do NOT always win game.
He has a bit of a learning curve, less so if you've never played him before. I'm still learning the right way to build his latest incarnation - I'm sad because I actually have to build tank now as opposed to relying on my shield.
I think he is still a very unique champion who is focused on team work. He's a giant friggin' scorpion, that's awesome to me. You just have to know this difference:
If you're jungling Lee Sin, you solo gank. This means you dive into a lane on an enemy champion when they're not expecting it and destroy them by yourself. When you Jungle Skarner, you rely on coordinating with your team. You have to tell your laner(s) who you're going in on and you have to wait for the right time and then, you have to attack together. Skarner lacks the damage output to solo gank (until much higher levels) However, he can successfully gank at level 3 with good coordination.
I guess what I'm saying is that you buy him because you love his concept and art and kit, and are willing to struggle to be good at him because he's awesome. You don't buy him because he's unstoppable and easy to use. I think he is just as good as any other champ, but you have to be good at him to achieve it, and a lot of people don't like champs you have to work to be good at.
Don't buy him if you're just looking to easily and consistently win jungle. Buy him if you like a unique champ who has seen ups and downs and largely kept his identity (except for his awesome passive, that's gone), and you want to show that you are willing to put in effort to be good at your champ and role.