Illustrator CS6 - Jagged edges when blending shapes, am I using the right tool?

I'm using Illustrator CS6 in Windows 7 64 bit with 32 Gigs of RAM. As seen in the pictures below, I'm attempting to make a smooth solid triangle with rounded corners.

THe first method I attempted was to draw a triangle, then effects > Stylize > round corners, but the corners were not rounded enough and were somewhat uneven.

The second method at first seemed to have perfectly formed the shape I was after when viewed from a distance.

https://i.imgur.com/hg58rPC.jpg

I first made the three circles to form the basic points of the object.

https://i.imgur.com/hDDW7W4.jpg

I then actioned the blend tool and clicked on each of the three circles, in particular the handle that appeared in the middle. I then doubled clicked on the blend tool to bring up options. I knew I didn't want steps, I wanted a contiguous shape, so I chose "specified distance" rather then "specified steps"

https://i.imgur.com/obb5wO5.jpg

Yep all good at first, then I noticed how illustrator was displaying all the blue lines of all the circles that the rounded triangle was made of.

https://i.imgur.com/Ec6LUvd.jpg

So I zoomed right into the edge of the shape, and realised to utter frustration, yes, the shape was made of several circles, rather then a contiguous shape, meaning all the edges up close are jagged, from all the little humps that represent the many circles.

Earlier I checked the below tutorial, but it pretty much mirrored the steps I've taken without success.

https://illustratorhow.com/blend-tool/

So in the end, is the blend tool right for what I wanting to accomplish, or should I need to use another tool? How can I blend two shapes to form a new shape without the jagged edges?