Just got the sample 15 second practice nock in the mail the other day. I won' t be able to try it out for a few days but Im looking forward to hearing what other think.
The one thing Im going to consider when seting up the arrow with these is Balance. The unit will add weight of course to the rear of the arrow. If I recall correctly the arrow should be weight forward about 12 to 15% Therefore once I have the nock installed I will have to see what weight broadhead to use to accomplish the 12 to 15% wf.
There is an interesting note and " how to " on broad heads at this link . See left side of page ..Broadheads


http://www.timberline-archery.com/default1.asp