I can think of absolutely no reason, besides cost,
not to try the 62/36/2 alloy having 2% silver, vs a more typical but less expensive 63/37 or 60/40.
The 62/36/2 alloy is eutectic, and melts at lower temperature than even 63/37. Silver has the highest thermal and electrical conductivity of any metal, so this alloy has better conductivity as well. Joints will not only have a smooth shiny surface, but a bright "color" as well, giving them a beautiful mirror-like appearance, compared to the shiny but slightly grey appearance of 63/37. The addition of the silver improves mechanical strength and helps prevent surface oxidation of the solder wire, improving shelf life. (I have a couple rolls that are several years old and still mirror-shiny). If you solder to silver plated terminals (
such as inside old Tek scope) then you must use silver-bearing solder to prevent errosion of the plating which destroys those terminals. The only negative I know of is cost, so if you can afford the one-time higher cost of the roll, then go for it.
You will not regret Kester 44 with size 66 (3.3%) core, no matter which alloy you go with.