I'm currently using ibill as the sole processor for an amateur teen paysite that I run (going to be switching to CCBill and adding an affiliate program for it soon though), and my ratio is consistently 1:250 or better. The membership fee is $19.95 with no trial. In fact, my ratio today was approx. 1:150. So in answer to your question, no, my signup ratios are not low
Cassie