Since Froyo, I'm finding it difficult to justify rooting my phone. However, I'm very intrigued by setCPU. Can setcpu be configured so that you see a general performance increase AND better battery life? Also, I'm not really sure I want to use anything but stock android. Can I put stock FRF91 on a rooted N1? What are the implications for future updates (will I get future OTA updates or will I need to wait for special versions of official android OS to be "hacked" for a rooted phone)?

If I don't go the stock android rout, what would I potentially lose out on (re: market, updates) by trying out CM?