There are many acts I like several tracks from so my top 5 will have to be based on their whole career and continued quality of works:
The Beatles
Pet Shop Boys
The Prodigy
Muse
The Smiths
other favourites include Breaking Benjamin/Red Hot Chili Peppers/Radiohead/Foo Fighters/Eels/Morrissey
and if my son's band continues with the quality of recordings I've heard so far they are also going to be making the list at some point:
Salvation, Salvation by Big Sixes