Hi
Looking to change the speakers in my Alfa 159 as they are starting to sound rubbish! Will be running off the standard HU for now but looking to upgrade HU and possibly add an amp.
Got a few on the short list but open to other ideas – budget £100.

Alpine SPG-17CS Alpine 1
Alpine SPS171A Alpine 2
Hertz DSK 165.3 Hertz DSK
Hertz ESK 165.4 Hertz ESK

Any help would be gratefully received..

I would go for Hertz, Sensitivity is a lot better. I would also budget for a £100 Alpine Active Sub, it is very good, almost too good to be true!

I`ve Used MB Quart components in the past and they are fantastic.
Better Amped, but still good run off a HU