Joe:
Might I recommend a Pfaff roller foot. Ive been using one for over 10 years and it works excellent. One thing to consider when selecting a machine is its capability to handle heavy hides. I would only consider machines that are rated at industrial or upholstery quality. My Pfaff is about 30 years old and it was used in a shoe factory. Needless to say it was built to withstand constant use. The roller foot wont grab hair like a traditional pressure foot. Also the machine mentioned earlier is designed for portability which means its built lighter than industrial models designed to be placed on a treddel table. Look on eBay at Pfaff roller foot with a treddel table. You wont be disappointed. seriously mine will go through three layers of steer hide like a hot knife through butter.
good luck
Jeff A.K.A. Kuduman