To add to the excellent comments already here:
with the 1015 you also get:
- on screen display (neato but not required)
- video up-conversion (if you ever plan on driving a projector or a nice TV of any sort using component video, but still have composite or s-video inputs from other devices I highly suggest this feature)
- in addition to the auto-setting of levels which the 815 gives you, the 1015 also adds a auto customizable parametric equalizer, which may help to make your speakers sound a tad nicer in your room.
Your money but its the way I'm going when my new HT room is done.
Lets chant together now, 1015, 1015, 1015...
~Josh