well wireless card for dragonfly

[Andrey N. Oktyabrski]

Good day.

I have a home router which is an old ThinkPad R31 laptop. Now it work 
with Atheros 2413 cardbus wireless card. The machine must be rebooted at 
least once per week because wifi AP stops.
Log contains these records about ath:
- ath0: stuck beacon; resetting (bmiss count 4)
- ath: ran out of descriptors

$ cat /etc/sysctl.conf
### ath bug workaround ###
net.wlan.force_swcrypto=1

I have tried to insert into the minipci slot two cards:
- Intel 2200BG - it probably works, but iwi driver do not support hostap 
mode.
- Ralink RT2561ST - it works fine, but wireless network stops in the 
some hours - maximum one day. Without any messages in logs at all.

What chip is a best choice for the dragonfly-based wireless access point?

P.S. For the reference:
ral0: <Ralink Technology RT2561S> mem 0x80100000-0x80107fff irq 11 at 
device 5.0 on pci1
ral0: MAC/BBP RT2561C, RF RT2527

ath0: <Atheros 2413> mem 0x90010000-0x9001ffff irq 11 at device 0.0 on 
cardbus0
ath0: AR2413 mac 7.8 RF2413 phy 4.5