The more money one spends, generally, the more precision, smoothness and durability one receives in return.

In the case of a bottom bracket, the expense goes up very quickly and the returns on one's money get marginal.

I don't mind spending premium bucks on a Phil titanium bottom bracket with alloy cups, mostly because at this stage of my life I have the money to do the weight weenie thing, and the Phil's allow me to fine tune my chain line.

I could get the same lightness, smoothness and reasonable durability for about half the price, but I couldn't get the left and right fine tuning.

I've ridden with some very cheap bottom brackets, and only one has failed me; and only then after a very wet, cold and dirty winter.

Doing it on the cheap has its own fascinations, and I admire anyone who can keep their bike going for pennies.
An art form in itself.

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As for how long it takes to do anything of a maintenance nature, I have found it best to triple my original estimates.

Everything goes more quickly and perfectly, with no unexpected interruptions or complications, when one imagines it in his head.