Sugden A21SE - rock music suffered

As quoted by Stereophile - is this a fair assessment?
Not into Creek or Naim. They add something to the sound IMHO.
Would a gainclone work for rock music?
Gainclones work. Use with efficient speaks. Yes, the Naim integrated swings. So do the Rega Brio and Exposure 2010S.
Creek IMO adds nothing to the music, just pure amplification.
If you are into Stereophile reviews, read the one about the Creek Destiny amp. Here is a quote:

"I can't comment on the timbral characteristics of the Creek Destiny because, across the entire frequency spectrum, I heard not a single deviation from neutrality—this is the least colored component I've ever reviewed"

It can be found online.