OpenBSD/octeon on USG-PRO-4?

[Philipp Klaus Krause]

For the Small Device C Compiler, I want to do regression testing on an
OpenBSD big-endian system. I have a Mac mini G4, but it is slow (I have
the version with the fastest CPU, upgraded it with an SSD and the
maxmimum of RAM). The RAM can't be upgrade beyond 1 GB. Buying an
Xserver G5 would be expensive, and they probably use a lot of
electricity. So I was looking at further alternatives.

Apparently the USG-PRO-4 is supported by OpenBSD/octeon.

Since the USG-PRO-4 has a relatively powerful CPU, I was considering
getting one for OpenBSD.

However, I wonder:

1) The RAM on the USG-PRO-4 can be replaced. What is the maximum that
will work on this hardware with OpenBSD?

2) The USG-PRO-4 has only 4GB flash. Apprently older devices (earlier
than USG-PRO-4 and with a slower CPU) had an internal USB stick that
could just be replaced to expand flash. Is there a way to get more
storage for the USG-PRO-4?

3) Howe powerful is the dual-core MIPS CPU? How does it compare to the
single-core G4 in the Mac mini or the dual-core G5 in the Xserve G5?

4) Is there a dveice supported by OpenBSD/octeon that has a more
powerful CPU than the USG-PRO-4?

Philipp