Fixed provides a much more efficient transmission, no gear worrying – you are always in the wrong one, you will stop thinking about pedalling. You will build fitness much faster and maintain it more easily. When I ride in a group in a medium chaingang, my HR is always in a higher zone than those on gears.
It’s just the best thing (as someone with a LOT of fixed bikes).
For the OP, if new, then the Dolan pre cursa or fxe (same geometry) is a very good alloy choice. I like my custom Kona PW as well. We also have a poo brown Langster, a Dolan Seta track bike (carbon frame) and an old steel track bike. AND… a fixed wheel folding bike which is huge fun too.
Yes I may have a problem. If buyng from stock, Dolan FXE.