I believe my "Why" is referring to the quote I quoted in my post #7 
I have not used the product you referred to and was interest "Why" you liked the solder.
Ah I see....
In the past I've used Kester-44 60/40, Ersin "multicore" and several others who's name I don't recall.
The Kester solder has stinky, smoky, messy flux which has to be cleaned off the board or else it absorbs humidity from the air, turns from dark brown to a light foamy brown (if you've ever seen the crema on espresso, that's exactly what it turns into) and worst of all, the tan colored slop is conductive (100K ohms or less!)
The Ersin also has smoky, stinky flux, but nowhere near as bad as Kester.
The others either have lousy flux or they're not perfectly eutectic (the alloy constituents freeze at different rates, resulting in a dull "cold solder joint" appearance).
Then one day I had to do a repair job on an ancient Tek oscilloscope that used silver plated ceramic bars as terminal strips. In order not to dissolve the silver off the ceramic, you need to use a silver bearing solder.
So, I bought a little roll of the Radio Shack 0.022 diameter 62/36/2 solder.
WOW was I impressed! The flux is VERY active, but it leaves almost nothing behind. The solidified flux is clear to light tan, and it doesn't absorb humidity.
The joints freeze perfectly shiny (meaning that the alloy is perfectly eutectic), the flux doesn't smoke up the room, and it barely has any odor at all.
All the other solders I've used gave me asthma attacks... I needed to use an exhaust fan with them... but not with the Radio Shack stuff.
Several months ago when it looked like RS was going out of business, I bought a bunch (50 to be exact!) of rolls of the stuff, fearing that I wouldn't be able to get a suitable replacement, and I had no desire to buy and try brand after brand to find a substitute.
But, RS is still in business and I've got enough solder to last.... well a few months at least!
