Be sure to do fry taste tests before stuffing any sausage. It will save you lots of grief.
In short, mix the meat with the seasoning. Take a small bit and fry it in a skillet.
If it's too salty or too strong, add more meat/fat to even it out.
If it's too bland, add more seasonings.
Don't worry if the meat doesn't taste exactly like what you are expecting. You are simply looking for too salty/strong or too bland and if it has a pleasant taste. The flavor will change by the time you stuff, smoke, and eat so as long as it is tasting good then you will get a good product in the end.
ALSO it is good to measure out the seasoning by weight (grams) per pound of sausage meat/fat. Teaspoons/Tablespoons, etc. do not scale well from 5lbs to like 20 lbs and such. But the weight of seasoning (grams) per pound of sausage meat scales perfectly :)
Just some tips of someone who has used store bought seasonings. I have no issue with them but you MUST figure out their measurement by weight and dial them in as their per volume measuring instructions don't scale OR their amounts are too much or too little. So just gotta work the kinks out is all... as with most things in life :)