Seems like the changelog of the 10.7.4 update mentions improved SMB performance/stability. You should try it out on a test disk/partition.lore said:OK no news so far so I've asked a friend of mine and he had the usb ethernet adaptor.
Tried yesterday copying 100 giga of files from a samba share (WHS2011) to lion.
The connection failed two times but I've been able to copy everything. I can confirm that Wifi with the real airport card is no way close to cable ethernet not only in terms of performance (well this is clear) but also in terms of reliability. Shares simply won't work using wifi.
Going to get the sonnet card.