I've been using both the WDR-3600 and the WDR-4300 with openWRT instead of the stock firmware for over a year now.
I like them a lot.
Price is great, range is good (no worse than my buffalo router that died on me - but I haven't tried a $100+ router and never will), performance is more than my needs require (streaming, surfing, etc.)
I run them as a primary router and then as an AP/network extender. For the first year with a wired connection between them, but now as a wireless bridge. In both cases, the performance has been excellent.