Neckreining has very little to do with the bit but more to do with legs/seat.

The only side pull worth buying is the Dennis Moreland one , all the rest are poorly balanced..

http://dmtack.com/sp38.html

Also..

http://dmtack.com/hackamores.html

Loping hacks..
http://cgi.ebay.com/Royal-King-Loping-Hackamore-Dark-Oil_W0QQitemZ260443174432QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3ca39f7620&_trksid=p3286.c0.m14&_trkparms=65%3A12%7C66%3A2%7C39%3A1%7C72%3A1205%7C293%3A1%7C294%3A50

"Blessed are the flexible for they shall not get bent out of shape"
"You can discipline and Discourage or you can Discipline and Encourage"
"Gentle in what you do , But firm in how you do it"