It's important to know how much data you'll be backing up. Tapes come in a wide variety of capacities, generally the higher the capacity of the tape, the more $$. THe capacity of the tape, along with the number of slots in the autolader will ultimately dertermine how much data your system can handle. Since this equipment is relatively expensive, don't forget about future needs. It may be wise to buy a system that is bigger than you currently need if your data will be expanding (whose isn't).