By rolling the Roth 401(k) to the Roth IRA, distributions from the Roth IRA are subject to the Roth IRA ordering rules where your original contributions (which were originally your contributions to the Roth 401(k)) come out first, tax and penalty free regardless of what you do with the money. After distributing your original contributions, your earnings will be distributed subject to tax but you can apply the higher-education penalty exception to avoid the early-distribution penalty.
If you instead make the distribution from the Roth 401(k) without rolling it over to a Roth IRA, each distribution is a proportional amount of contributions and earnings so some portion of each distribution will be taxable and subject to the early distribution penalty. The higher-education penalty exception does not apply to distributions from a 401(k), it only applies to distributions from an IRA.
The fact that you started the Roth 401(k) more than 5 years ago is irrelevant since you are not yet age 59½ or disabled (indicated by the fact that you are concerned about the early-distribution penalty). Also, if you roll the Roth 401(k) to a Roth IRA, your holding period for the Roth 401(k) for determining qualified distributions does not carry over to the Roth IRA. Your holding period for determining qualified distributions from the Roth IRA is established by the first year for which you make a Roth IRA contribution (including a rollover contribution or Roth conversion). So if you are within 5 years of age 59½ and have not previously had a Roth IRA, you might want to consider not rolling the entire Roth 401(k) over to a Roth IRA (but I suspect that you are much more than 5 years from age 59½, so this would not be a concern).
