Homebrew PCBs

A previous poster made the following comment:
    I did 'em myself using Radio Shack FeCl³.  I tried Ammonium
    Persulfate once, but NO WAY at home, ever again!  Whew!

I had used messy ferric chloride when I made some hobby PCBs about 25 
years ago, but I have seen other less-staining etchants are now 
available, such as ammonium persulphate and sodium persulphate.

What are most people using at home, and what are the pros and 
cons of the various etchants?  Cost?  Shelf life?  Ease of use?  
Safety?  Cleanliness?  Availability?

WT
Winnipeg, Canada