I had a Kenwood Sirius box like that. I bought it used, it had service, and worked for years without me ever having subscribed. The sound quality was pretty good back then, too. (2005 or so.)
Then, I changed head units to one with built-in XM, as I preferred their lack of DJ's. But, they merged with Sirius shortly thereafter, and adopted the noisy talky format of Sirius.
I got a new car last year with Sirius built in. But, the audio quality of Sirius now is just awful. Unlistenable. I finally cancelled after the trial and promo pricing period. (Just call to cancel, and they give you 6 mos for $25.) But, even at the promo price, it's hard to justify, if I can't listen to it.