using 2 E3000 with DD-WRT in bridge mode (using 2.4ghz side as the access point and 5 ghz for the bridge mode). get 8 megabytes/sec transfer rates to my NAS box in the basement. no issues with them at all for the last year
I have the step up with the N66U and it works great and appears to be very future proof. The asus routers have been great for me so I would think you'd do OK with the 53u.