There are two choices in the Sirius XM lifetime subscription promotion:
$100 off the Lifetime Subscription, or $150 off the Lifetime Subscripton + The Best of XM Package, bundled.
It's unclear how long the Sirius XM Lifetime Subscription discount promotion will last. Also, as far as we know, it's only "redeemable" via phone, at (866) 519-7474.
Sirius Satellite Radio and XM Satellite Radio completed their merger in late July. The two had been in limbo for 16 months prior to the narrow FCC approval, of 3-2.