Hi Matt,
My ST 60 is very quiet with the stock muffler. I received another Merco 61 today, on the back plate is scratched R S. I wonder if this is one of the famous Mr. Randy Smith that has a birthday today??? The engine is very pretty but its one of the heavier Merco's, not sure what I'll use her in. Most of my Merco's are the lite case, two ounces lighter than the newer Merco. (Lite Case 11 ounces, regular case 13 ounces) Also the venturi size is different on a lot of the Merco's. The square bottom case has a smaller opening than the lite case. Both seems to use around the same amount of fuel. I even have some merco with a dykes ring. My best Merco's are the ones with the dual rings. They seem to have more power and will run a little higher rpm's. They are such a pretty motor, Chrome looking heads, some black heads, can't remember what other colors they have for the Merco's. The Merco has its own sound and if you like the sound of the tigre, you'll like the Merco also, Gary