FreeBSD 6.0 as storage server with raid5?

[Torfinn Ingolfsen]

I need to set up a storage server for my personal use. The current
solution on my little local network is a haphazard collection of old
machines with disks in them, and backups are so-so.

I could just set up a "normal" FreeBSD server, with single disks, and
setup another one for the backup. However, I would like to try something
new for me; raid. Specifically, I'm looking to set up a server with raid
5 for storage.
For the backup server, I haven't decided yet, but I am thinking about a
normal server with external (firwire or usb 2.0) disks.

 I was thinking about gvinum for the storage server, but given the
current documentation and the discussions about it now, I don't want to
risk it. So, I'm looking at hardware raid 5 controllers. From this list,
it seems that areca and 3ware are the best ones, but they are very
expensive here. I also know that anything with a SIL 3112 on it are to
be avoided. So here is the list over controllers I can get for a
reasonable price: Highpoint RocketRAID 1640    (4 ports)
Promise FastTrak S150 SX4    (4 ports)
Promise FastTrak S150 SX4-M    (4 ports)
Highpoint RocketRAID 1810A    (4 ports)
Highpoint RocketRAID 1820A    (8 ports)
Intel RAID Controller SRCS16    (6 ports)

Which one should I get? 
Are there some that are not supported or should be avoided for other
reasons?

Other questions:
1) can I install several 4-port RAID controllers in one machine? I can
    get two RocketRAID 1640's for the price of one RocketRAID 1820A.

2) Rebuilding a damaged array - are some of these controllers "better"
   than others? (Easier to handle, rebuilds in shorter time, ?)
3) disks - I understand the importance of using disks from different
   production runs. Some people have suggested to use disks of different
   brands as well, but there were no conclusions. Should I stick to the
   same brand and model, or can I use disks of different brands as long
   as they are of the same size?
4) PSU considerations. How big a PSU do I need if I want to run two
controllers and eight disks in one machine? are there any rules of thumb
for sizing this?

Other suggestions are welcome.
-- 
Regards,
Torfinn Ingolfsen,
Norway