Lukas Beeler over at his blog on midrange.com has a close look at the System i 515, one of the new System i machines that IBM announced in April. He talks about the machine lacking a front door (which the 520 has) and how adding memory can give you a migraine. But he does add that IBM has preloaded the console configuration correctly so you don’t have to bother with reconfiguration yourself if you’re using a thin console.
In the end, the 515 isn’t really a new machine, just a new licensing model which lowers the price for the System i a little bit for smaller businesses. While this might entice small businesses already running a System i to upgrade their hardware, I do not believe that IBM will be able to acquire many new customers without improving performance, lowering prices and improving remote maintenance access.