So I'm looking to build a new frame up. The frameset did't come with a head set. I was going to go with whatever the cheapest head set my bike shop have available, but the mechanic recommended a king. I understand that the king head set will probably last me a life time, but is it worth it? I've had my road bike for 3+ years with roughly 16k miles one it. It's still on the original generic made in china sealed bearing headset.

This mechanic always gave me great advise. I'm not concerned with weight with this build. It's hard for me to justify spending $100+ on a headset. What's your thoughts?

Get something cheaper. A King is nice but not worth it unless you are breaking other headsets or really need to abuse it. Even then you should consider whether it is cheaper to just replace the headset every time for ~$20 or spend 6+ times that much for a King.

That said, I have a King on my MTB, but I have broken a few headsets on other MTBs. Plus this is a classic ride and it kind of deserves a King, imo. If it were a different beater bike, it would get whatever was decent and on sale.

The King is great but not at the price. A Dia Compe or FSA will be very durable at 1/2 to 1/3 the price.

I'm thinking going the cheap route. This is going to be a commuter. I don't really take my road bike in bad weather, so no wear/tear experience in this field. Is this something to consider?

The headsets HillRider listed will do just fine for your purposes. Also, since it is a commuter and probably has more exposure to theft, you won't be as upset if it is stolen and you have not lost alot of bling parts.

As I understand it, the real use for a Chris King is on a mountain bike where you get lots of off-axis force. Otherwise, they look cool but you have to care about that waaay more than I do to get your money's worth that way.

You always pay a lot more for a small improvement at the high end of the market. And the King headset will bind up if you install it in a frame that hasn't been properly machined. But if you don't mind the initial financial hit, you'll save money in the long run if you ride enough. The King headset will never wear out as long as you keep the bearings clean. And that can be done without ever opening up the bearing itself. Just keep a bead of grease on the outside of the seals. It takes ten minutes to wipe that off and regrease once a year. The headset should outlast many framesets.

If it's hard for you to justify, then don't get a King. Chris King headsets are luxuries, not necessities.