I was lucky enough to get this Merriam's a few weeks ago on my quest for the Grand Slam of turkey. Washington state has three sub-species of wild turkey: Merriam, Rio Grande, and Eastern. Check out the National Wild Turkey Federation for breakdowns of the different Slams.
For all of you die-hard turkey hunters check out this video of Sadler McGraw. Sadler is a World Champion and makes a very convincing argument for the use of friction calls.
Also check out this great article: Turkey caller Sadler McGraw Living Up to the Hype