What I like the most about Quantum's new libraries is that they can be stacked to form a larger unit that is truly the sum of its parts -- it draws from all the drives, slots, and robotics of its components. This beats the old approach of updating a library with more drives and slots, because you can now do it yourself, without the cost of summoning a field engineer from Quantum. I haven't tried this yet, but according to Oade, the update is a breeze: You remove the top cover of one library, place the new library on top, and align the two units by inserting screws into predrilled holes. Add a new component, a sort of double-entry mail-slot used to exchange cartridges automatically between units, power on, and you're ready to go.
You can stack PX models in any combination, up to a 40U tall tower with 22 drives and 440 cartridges, but the largest configurations may require some heavy lifting -- and I mean real muscles. Interestingly, you can remove a unit from a stack and redeploy it somewhere else, again, without outside help.
According to Oade, a PX502 in the minimum configuration should sell for less than $12,000. but if your budget falls short of that, the new rack-mounted SuperLoader 3 sports 16 slots and one out of a variety of tape drives and can be had for about $4,000. Just don't expect to stack that unit.
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