Choosing a UPS - yet another headache!

Hello fellow forumgoers,
My perfect UPS looks something like this:

1) Completey silent during normal operation
2) Perfect sine wave (with a Corsair HX520 PSU do I need this?)
3) At least 4 x FR/Schuko sockets
4) LAN cable surge protection
5) 1000VA or more
6) USB management
7) Linux management software
8) Black (if it's perfect it has to be!

The silence requirement is very important because I'll be sleeping about 3 feet from it. Don't want any humming or fans spinning all the time.

I have some other questions:
- Should I be looking for a line-interactive design? I read in one of APCs whitepapers that they generaly don't need much if any cooling and therefore chances are there won't be any spinning fans.

- What does a "stepped sine wave" line-interactive ups mean? That it outputs the stepped wave all the time or only while on battery? If it's the second case than my range of options expands greately.

- I have an Altec Lansing MX5021 set of speakers and they hiss even when they are the only piece of powered equipement (no sound input) and the volume is at 0. If it's common mode noise or something like that maybe a nice since-wave nose-filtering UPS will fix it?

So far I'm looking at 3 models:
1) MGE Ellipse MAX 1100VA (stepped sine wave)
2) MGE Evolution (perfec sine wave, no LAN surge protector)
4) APC Smart-UPS XL 1000 VA (perfect sine wave, no LAN surge protector, no Linux sofrware?)

Anyone who owns one of these - please share your experience!