As far as power goes, they're both 95W TDP parts. You have a low power 8-core vs a normal 6-core (or 4 core vs 3 core, depending on what you consider a core). The 8320e is also newer so boards may need a new BIOS update to support them - odds are this isn't a problem, just something to look out for.
For OC and lifetime... I think it's generally accepted that OCs *do* decrease the lifetime of a CPU. However, the relevant questions are
1) Decreases it from what?
2) Decreases it by how much? (Or equivalently: Decreases it to what?)
Thing is, CPUs last a long time. Decades is common, so unless you're planning on this being your last build until 2030 or so you don't need to worry about it. Even if you decrease it by half its lifetime, it still has many many years of service. In practical terms, I've never seen a CPU fail to work properly due to a stable OC that was held for over a year. Dead due to a very high OC - sure, that happens, that's why I specified stable and used for a long period of time. Don't be dumb about the OC and you'll be fine.