The Kovalevs I have play more like 5.25 to 5.5--slightly higher than the Warrior Gionta. The heel starts low, but it swoops up quick. A quarter to a third of the way from the heel to the toe, it's already above 5-5.25.
The Leinos I have play lower, like 4.5. That pattern's also more open.
What ever happened to the Kovalchuk pro curve? There was a video with Ronning talking about that one a couple of years back. I'd be into that if it got developed.