Budget, existing expertise with a meter and proposed avenues of use further down the line, together with the choice of either analogue or digital will see what you end up with. What works for others here may not necessarily work for you. My personal choice is a Sekonic L758 for its speed and versatility. But I've also angled toward an old Weston. I think primarily it is a question of budget because a meter can be obtained from around $130 on the second hand market to more than $1200 new.
At any particular point in time, the meter brand of choice was...
Gossen (back in 60's and 70's)
Minolta (back in 80's and 90's)
Sekonic (in the 2000's) -- after they made their meters more like the Minolta user interface and Minolta left the meter market
So on the used market for flashmeters I can highly recommend the Minolta Autometer IV and V, the Minolta Flashmeter V and VI, the Minolta Spotmeter F, which typically get overlooked because today's photographer so often has only heard of the current Sekonics.
Kenko now markets the Autometer V and the Flashmeter VI under their own Kenko brand name and with new model numbers (the Autometer V is now the Kenko 1100).
they are great metwrs. i've used them for yearswith grat success,outside and in the studio!