Definitely not permanent. Not for me anyway. I did that, and i re customized all my screens etc, just for the restarts to start again within a day or two. I can say that over time the Sense restarts have been happening significantly less often. Sometimes I can go a few days without one. Overall i say I average 1 a day, which is better than several times a day at least. I've heard a factory reset might work, but with no guarantee im not gonna go through that trouble. I been told they test these updates on clean factory phone, so the only way to get it perfect is to duplicate that scenario.
Unfortunately, the only real solution is buy an Evo 3D.
This has been my experience too. The restarts started happening again after a couple of days. But, very infrequently. I can live with it, but I suspect it'll get worse over time.