I don't do life cycle funds. I simply do not like them. No particular reason. I guess I like a little more control...
I do have some indexes. There are a few reasons why I like them. More actively managed funds can provide greater returns, but tend to have higher expenses. Are they worth it? It all depends on the skill of your funds manager, and whether or not you picked the right kind of fund family. Did you buy a growth fund when growth was in???
Indexes, by definition, are pretty average. They are intended to mimic the appropraite index (dow, russell, etc). You should see relatively average returns. Expenses are usually low. Over teh long haul a lot of basic index funds have done as well as many of the more actively managed mutuals.
I'm a believer in diversification. I own some indexes.