Out on the range, Titleist Brand Ambassador Jimmy Walker gives his new Prototype MB irons a first test run.

Here's a close-up of Jimmy's new Prototype MB 5-iron.

Titleist Brand Ambassador Kevin Na gives his new Prototype AP2 irons a closer look.

The new Prototype AP2 irons are already in the bag of Titleist Brand Ambassador Scott Stallings.

Scott played 36 holes with his new irons Sunday, and 18 more in Monday's pro-am.

"The new ones are in the bag," Scott said, " no question about it." (For more reaction from Scott, check out today's Team Titleist Tour Blog post.)

Marni Ines of Titleist Golf Club R&D delivers a few more sets to the Titleist Tour Van.

Titleist Tour Rep Scott Cuppett brings a set of new Prototype MB irons out to the range.

Greg's new Prototype CB's were the only left-handed set on the range Monday.

And here's a right-handed set of the new Prototype CB irons being worked on in the Titleist Tour Van.