It occurred to me that Andy Ruhl wrote in gmane.os.netbsd.general:
> On 9/22/05, Martijn van Buul <martijnb@atlas.ipv6.stack.nl> wrote:
>> It occurred to me that Andy Ruhl wrote in gmane.os.netbsd.general:
>> > On 9/19/05, Andy Ruhl <acruhl@gmail.com> wrote:
>> >> Is anyone using the atu driver with a USB 801.11b adapter? If so, I'd
>> >> like to know what adapter it is.
>> >
>> > Didn't get a response, 1 more try and copying netbsd-help this time.
>>
>> Sorry, I must've missed it.
>>
>> I used to be using an USB atu device indeed - I was using an SMC2662 V.4.
>> However, I wasn't very happy with the performance of it, so I switched to
>> using a Cardbus card using ral(4).
>>
>> However, I still have the SMC 11b nic, so if there's anything you want me
>> to do..
>
> Any idea if the performance problem was related to the adapter or the driver?

I'm not sure; it's probably a combination of both:

1) Reception dropped off really fast. Using the same access point, the 
   atu device had mediocre reception unless I was in the very same room as 
   the access point, compared to my current ral(4) device. To put it this way:
   unless I was sitting almost next to the access point, it would always be a
   bit of a gamble whether I could get a usuable connection. The ral(4) 
   device just works (TM). I don't think this is a NetBSD specific issue,
   as I had the same problems under Windows.

2) Running NFS over wireless using the atu device was next to impossible,
   even when using NFS-over-TCP. Reducing the blocksize helped, but only a
   little bit. Same applies to samba; it just wasn't reliable, leading to
   rather nasty stalls all of the time. Using the same samba mounts under
   windows *did* work good, so I'm not sure the NetBSD drivers have nothing
   to blame. For the record: NFS over my current ral device works like a
   charm. I can still compile a kernel over NFS when I'm sitting in the 
   garden when using the ral(4) network card. Using the atu(4) device, 
   chances that trying to play an MP3 while in the same room as the access
   point will likely result in a stale NFS mount.

> I'm mulling over getting one of these so I have a fairly complete
> "toolbox" of usb devices which work under NetBSD.

Well, maybe I caught the "bad specimen", but I wouldn't advise them to
anyone.

If someone would like to pick up the challenge: I'll happily ship my
USB atu card to whoever feels like (s)he could impove the performance of
these critters.