Harmonix had previously hinted that DLC for Rock Band 3's "Pro" mode would a bit more expensive than the vanilla offerings because it required "a lot more work to do." Speaking with IGN, MTV Games' Paul DeGooyer clarified exactly how the pricing will differ for the upcoming sequel. He explained that "all DLC released for Rock Band 3 will be fully Rock Band 3-compatible, which means it'll come with Pro Mode for keyboard and drums, harmony mode, etc." However, Pro Mode for guitar will be sold separately. "If you're not interested in Pro Mode for guitar, you can still get the DLC that should conform to our current DLC pricing, and you get Pro Mode for all your other instruments."

The cost of Pro guitar will be $1, the interview reveals. "The alternative would be of course to include it (in the regular download) and up the price for everybody, which I don't think is really fair," DeGooyer argued. Additionally, he reveals that not all DLC tracks will even offer Pro notes for guitar, saying certain bands' "guitar parts wouldn't rise to the level that they would need to have pro mode authoring associated with them." Ouch.

There are plans to retrofit earlier DLC with Pro tracks, however DeGooyer was unable to clarify how the process would work. Apparently, the studio is having trouble making a system that "recognizes people who have already purchased" DLC in order to "be able to supply the updated file at a discount."