A 401k without some matching shouldn't be called a 401k in my opinion. You'll have to weigh the pre-tax advantage vs. the limited selection of funds available in the 401k offerings and 10% early-withdrawal penalty.

If I had some unique situation where I wanted money more accessible, I'd forego the 401k and get into an IRA with Vanguard, with one or more index-tracking ETFs (VTI i think?). But, I'd make sure its done every single payday automatically and directly. No stop off at the savings/checking account.

*This is not professional investment advice.