Not a problem Nemo's Janitor
Why did you use in your rock bin and not your tank?

I use it in my rock bin because i am cooking my rock and i don't have a tank up and running at this point. I won't be able to setup a tank till next year after the move.
The parameters you measured are "what" . Consistent can be good and bad.
Here are the parameter I tested couple months ago when I received the first bag of tunze salt
Salinity: 35ppt (Refractormeter)
Temp: 78F (Ebo Jagger 250w heater)
Ca: 450 (Elos)
Mg: 1300 (Elos)
Alk: 9 (Elos)
PO4: 0 (Hanna)
NO3: 0 (Elos)
K+: 360+ (KZ Kalium test)
Here are the parameter from the bucket I got at RAP.
Salinity: 35ppt (Refractormeter)
Temp: 78F (Ebo Jagger 250w heater)
Ca: 440 (Elos)
Mg: 1320 (Elos)
Alk: 8 (Elos)
PO4: 0 (Hanna)
NO3: 0 (Elos)
K+: 360+ (KZ Kalium test)
The number change a bit but it will not affect the coral because the change isn't that big plus you only do 10% of water change. Another reason for the number to be different could be user error… Consistency between batch to batch is a good thing
Give a comparison of IYO to say the mix you use in your pride and joy tank and one or two others.

No i do not expect to put you on the spot, just an honest, no brand naming review.
I have use several brand of salt in the past:
I am not going into detail with the comparison or what I like or dislike about it because it will turn into another "which is the best saltmix" type of discussion some how it will get out of hand and ended up being locked down. But i can tell you my two favorites salt is Tropic Marin Pro and Tunze because their parameter pretty much similar.