I really want to use this type of product but I have questions. I have never used them before.

I take it these take the place of the inserts that come with a set of arrows and you glue them in, is this correct?

I will be using Beman 400 series arrows unless some thing unforeseen changes my mind and Magnus 125 gr screw in broad heads.
I was hoping to be able to change the weights on the inserts in increments of 25 gr or so till I got to an arrow weight I really liked is there any way to do this?

It appears to me that if I use the brass inserts (discussed above) I have to pick one and glue it in, if I don't like it I'm stuck with it because it is glued in. Is this correct?

Changeling