Tom, what benchmarks did you see for the Infrant that showed them near the top? I've only ever seen tests that show them near the bottom. In fact all SoHo NAS solutions were abysmal for speed at only a fraction of the data transfer rate of external USB or Firewire devices (even when connected via an all Gigabit path).
I'd like at some point to have a robust NAS solution, but I don't see anything that really makes me want to jump on it yet. For no I'll stick with he Mac mini running a couple of external drives (one for media streaming and a dual drive RAID1 enclosure for backups). TIme Machine in the new 10.5 version of Mac OS can't back up to NAS devices either. The only network drives it can hit are those connected to another machine running the same OS and formatted HFS+