I don't think age has any effect on whether a target date fund is ideal for you or not, since they make target funds for all kinds of retirement dates.
The question would be whether your balance is big enough to diversify. If you're not too comfortable on how to choose a basket of funds, I'd be okay putting $85k in one Vanguard target fund. If you want to diversify, I'd look at putting the bulk in a good core fund (such as Vanguard Total Stock Market Index, which owns the whole market). Then you could open up smaller funds such as International fund or a small-cap fund. And you could put a small amount in a bond fund.
The Vanguard Target Date funds hold their other funds (such as the Total Stock Market Index Fund, etc.)
If you don't have the time or knowledge to actively manage your account, I see nothing wrong with using the target date fund. I like Vanguard and think they are a good shop.
I put DH's SEP IRA in a Vanguard Target Date fund.