Morning Star, I try to work my bows to a certain point-on. Although I shoot without consciously seeing the arrow, I do know where my point-on is....about 55 yards. Keep in mind that I anchor with index finger corner of mouth, and back of hand/thumb in my cheek bone and use a dynamic release...not static. If you shoot three under, or use static release, you will probably have a much shorter point-on.
Some bows are a little faster than others...some slower, but much adjustment can be made through brace height, string type, etc. If your bows are close to the same weight, it shouldn't be too difficult.
What you need is a constant....that's why I use point-on to judge my bows. You could also use a cronograph if that is available.