Why are people not picking Stormraider's that often?

I think it's an amazing mastery and it can be used on a LOT more champions than it currently is. Like people only really know it on and maybe but I think there are some other champions who alo can make tremendous use of it but you just never see it on them.

For example, what is known for? Dealing a ton of burst damage every few seconds or so with his barrels. When do you want to pick Stormraider's? When you have burst damage available to you every 10 seconds! It's just perfect for him, I can't see why you would use it over Thunderlord's, especially since Thunderlord's is so hard to proc because you have to get into melee range for it.

Then there's , another champion on which people primarily use Thunderlord's even though he has enough burst already and since he has 0 mobility and really shitty base stats he really almost kind of needs the extra movement speed for Stormraider's, it's a perfect match.

And these are just the two examples that really stick out to me personally, there are a lot of other champions on which it should be really good on: