Take the FREE MONEY
I have to agree that the 50% match is free money. 50%, even though it only applies one time, constitutes years of growth even in the best conditions.
My own personal style is to max out the 401(K) up front - i.e. I fund the full $19,500 in the first few months of the year. It makes for an irregular paycheck, but it locks in the contribution even if I lose the job or change jobs to a company without a 401(K).
There are 2 tax categories here: Traditional IRA and 401(K).... and Roth IRA and 401(K).
There is a gotcha with a traditional IRA or 401(K)
Since you're not paying taxes today, you must pay taxes on withdrawal or conversion - and that can be an extreme burden late in life.
Now, the mathematicians in the crowd say "well, your tax rate will be lower in retirement" - snort those mathematicians haven't spent a lot of time in skilled nursing facilities. Here's what REALLY happens.
With a traditional IRA/401K, you (read: highly competent saver who did everything right) find yourself with more IRA/401K than you have bankable lifetime. You have 2 bad choices:
- Distribute from the IRA at a faster rate than you were hoping for, into other investments -- pushing yourself into the same tax bracket you were in while you were working.
- Fail to distribute enough from the IRA while you are healthy, and start having medical problems that necessitate distributing at a very high rate - pushing yourself into an even higher tax bracket than when you were working.
The cure for all these problems is Roth. With a Roth, the taxes are pre-paid, so the large withdrawals have no effect.
Take the free money anyway
Even so, the 50% FREE MONEY is way, way more than enough to pay those awkward taxes five times over and then some. So a traditional IRA/401(K) with a 50% match is still a better deal than a Roth anything with no match.
Seek the best of both worlds: Take the 401K with match, then convert to Roth 401(K) at some happy future date, e.g. in the event you take a gap year.