I bought second-hand a Gossen Multisix (hand-held reflected light and incident light exposure meter) and a Minolta Spotmeter F (hand-held spot reflected light e.m.). They are OK but, frankly, an integrated solution like the Sekonic L-758 would be much more practical.
So if money is no object and if one wants to buy new, and has slides in his photographic habits, I would go for a "do-it-all" so that the expense is made only once, it takes less space in the bag etc.
Overall I think that a spot lightmeter is useful only when using slides, or when using the zone system. So for most photographers it is not necessary until the day when they regret not to have bought an integrated one