Regarding the R10 vs. L3000, I agree with most of the impressions posted by mulveling and markl in their respective threads.
mulveling:
R10 vs Qualia vs L3000 vs HP2 vs DX1000 Review - Determining my "King" of dynamics
markl:
IMPRESSIONS: Sony Qualia, Audio-Technica L3000, Grado GS1000.
I like the L3000 very much and considered it my top two favorite along with the W5000. The L3000 does many things better than the W5000, but I preferred the W5000's soundstage, imaging and details.
The R10 seems to have the L3000's and W5000's strengths and few of their weaknesses, if any. Switching from the R10 to the W5000 was a bit of a shock. The W5000 sounded thin, cold and unnatural!?!

As some of you may know, I've posted about the W5000 before and it has been my primary headphone since early 2006.
The W5000 is paired with the AT-HA5000 and the R10 with the RSA Raptor. Source is a Chord DAC64.
I consider the R10 my current favorite by a significant margin over the L3000 or W5000. It just sounds
right.