Welcome back to the Amiga!
I've only got experience with an XSurf Mk 1, but the Mk 2 is very similar.
Here's my thought on your networking options:
The XSurf will give you some "bonus" (non-bootable, burning to a CDR drive on one of these ports is also not recommended) low-end IDE ports, 2 clock ports, and a 26pin connector for something like a highspeed parallel or serial port.
The Algor/Norway will give you USB ports and the extended boot rom.
Since you've got a Powerflyer (and motherboard IDE) the XSurf IDE ports don't seem like they'll be of much use to you. Neither does the 26pin port, since I'm guessing you won't need serial and parallel for much due to your Ethernet upgrade.
On the otherhand, the XSurf is MUCH cheaper than the Algor/Norway combo.
Basically, does the added cost justify what you're planning to use the card for?
