re: Rebalancing Investing Accounts

For what you are talking about, there is no difference in fund choices in either Roth or 401k.

Given the same investment choices in either, will give the same result.

The differences comes in on: the tax rate paid on the money put into it, and the tax rate in retirement for a given amount of withdrawals.

Roth is better if you are lower now than in retirement (typically those just starting off)