A budy of mine was shopping M5s and I suggested he look into a CTS-V. He ended up getting an 05 V with one year of warranty left on it for not more than 25K.
Overall I don't think it is nearly as nice as the 5 but upkeep has been nothing and with the Borla exhaust on it it sounds sooo nice.
He and I went to one of the GM Auto Show in Motions when the C6 vette came out and we got to drive both the vette and the V, we both liked the V better and that has stuck in my head ever since.