He also has only hit 20+ HR's in season twice: 20 in '09 & 22 in 10'.
Frankly, I really don't think you're getting that much with more with Choo:
Choo 2012: .283/.373/.441 wOBA .360
Ross 2012: .267/.326/.481 wOBA .341
And in that trade proposal for Choo, the M's give up Paxton AND sign Choo for $34 million for 3 years (essentially $45 for 4 with arbitration).
In that scenario the M's are paying about $11 million a year for a player I'm not even sure is better than Ross - who should cost close to half that amount. Throw in the the loss of Paxton (for a player we shouldn't have ever given up in the first place), and I'd rather spend money on Ross.
So, slightly worse might be right. But if he costs $4 or $5 million less a year, isn't that worth it?