Have had my Evo in a Seidio Innocase II and Clip since day 1. Have dropped it several times (I don't baby my phone - that's the point of the case - I don't abuse it just normal wear) and have only made nicks in the case. Never a single issue to my phone. Drops from my waist (3'), shoulder height (5.5') and from inside my Nissan Armada to street/pavement a few times (4-5') and no Evo issues.
I see a lot of people say the Evo is fragile, but with this case it's held up quite nicely.
I still don't have any scratches or paint wear from the case like others, and I wouldn't even care as long as it prevents true damage. I never take the case off anyway.
BTW, if you case broke from a fall, contact Seidio directly and ask if they can replace. They might not, but they also might. I've had good experience with them via their account on this forum. Seems like an actual broken case might be cause for replacement.