Hello hpuxrules,
If you have yet to purchase it you might want to consider the HP-EMLe instead. It is the HP badged version of the Sun SL500, but uses HP firmware so that the the library can be managed from CVTL and L&TT software. If you buy the Sun version you are locked into Sun maintenance. Third party maintainers can do the hardware OK, but Sun only offer firmware upgrades for Sun maintained machines. HP are much more open and publish everything you need on their public web site.
Also, if you are going to stick with LTO4 for a few years, then the STK L700 or STK L1400 supports LTO4, is maintainable by anybody, and costs buttons these days.