I recently upgraded from a WRT54GL with Tomato to an RT-N16 with TomatoUSB (newest)
Doing wireless transfer tests via Air Sharing and a 130MB file. It took an average of 60 seconds on the WRT54GL (~17mbps) it is taking an average of 90 seconds on the N16.
It also appears that both the iPad and iPhone 4 are connecting at 54mbps and never going higher, while my macbook pro connects at much higher bitrates. Since both devices are 802.11n, it seems like they should be connecting at higher bitrates, and if I set the router to "N only" they will not connect at all