If you plan on using prod modules, beacons make sense. It also helps with ups. The power of speed beacons is that it reduces the number of machines you have building something. The power of prod modules is that it reduces the number of input materials needed to build an number of equivalent items.

Do beacons effects stack Factorio?

Overall effect stacks with multiple beacons covering the same machine. However, a beacon allows transmitting the effect of a module to multiple machines and the effect of all beacons in range of a single machine stacks. ...

Are speed modules worth it Factorio?

Speed modules might be the least useful of the bunch, because most of the time it's easy to achieve more speed (more efficiently) by adding additional assemblers/furnaces. If you have a bottleneck situation where you absolutely can't find room to expand, speed modules are can be a decent quick-fix.