I ordered the AC Spacehorse Frameset in Mint Green. I am going to build it as a day use light gravel bike. Shimano GRX probably.

I need a good headset. I searched the forum thinking surely someone would have asked this question but to my surprise did not find that it had been ask. At least in the last couple of years.

Headset Specs: Upper EC34/28.6 Lower: EC34/30

I was looking at the FSA Orbit MX but don't really know if that is a decent headset for the money.

I would appreciate some ideas on a solid reliable headset ... nothing over the top. Any suggestions?

Cane Creek 40.

This is my recommendation, also. Pretty easy to install, good quality with durability, sealed unit keeps the maintenance low. I have them on 4 bikes, 2 of 1 1/8 inch, 2 of 1 inch. The 1 1/8 inch is the same specs as mine.
Also, replacement parts, like seals, are available.

If you want high end MUSA Bling: King NoThreadSet or Phil Wood or White Industries
If you want high end really nice also MUSA less blingy: Cane Creek 110
If you want blingy MUSA:: Wolf Tooth Components
If you want a good reliable reasonably priced: Cane Creek 40

FSA, Ritchey and others make fine serviceable headsets but Cane Creek is my go to for headsets generally. I have 5 Cane Creek 110s, Three Cane Creek 40s and Two Chris Kings GripNuts (for my threaded stuff). The only other headset I think I have is a Acros that has block lock or similar and I have a frame that is running a White Industries but I am selling most of that bike and was an old project. Oh and one Specialized bike that has I think FSA integrated bearings which I would love to replace at some point but they are sealed and no issues. The big problem on that one is it is an odd size and I cannot find the correct bearings from Cane Creek or Enduro or similar at least not easily but I haven't searched high and low yet.

I also run Cane Creek eeBrakes on two bikes and one of their eeSilk seat posts and have used other parts from them so I really do love CC and they are super nice and helpful.

That about sums it up. I would only add that even the Cane Creek 10 is pretty solid; that headset came on one of my bikes, and it's still fine after about 15k of all-weather mileage with no service whatsoever.

But yeah, the CC 40 is as good a headset as anyone really needs...Though that didn't stop me from putting a 110 on my gravel bike.

All good recommendations above. I’ll add that I’ve used the Orbit MX for years and had no issues. Pretty great for the price.