If you can't afford the HDX (it's rather salty in price but well worth it) QAD has a good selection in drop away's that are a bit cheaper. Not as many bells and whistles as the HDX but still VERY functional and quality rests. The LD-Pro series comes to mind, about 40 bucks cheaper than the HDX.
http://www.lancasterarchery.com/qad-...est-black.html
Another option is the Ultra-Hunter at 55 bucks here
http://www.lancasterarchery.com/qad-...rrow-rest.html
Another good quality rest is the Rip Cord
http://www.lancasterarchery.com/ripc...est-black.html