Regarding "a great feeling," it certainly is.
Due to the generosity of so many Aussies, I have complete collections of almost all decimal coins. But mine came from trade, gifts, and purchase.
It must be an even greater feeling to have collected an entire set on your own.
I was trying to think of any of my collections that I completed totally on my own. There aren't any. The closest one would be my Kennedy Half Dollars, but recent ones had to be purchased, as well as the 1970 D.
Regardless of how you get them, a completed set is super.