Audible Illusions M3B or L3

I'm planning on getting one of these two preamps. Has anyone compared the two? Are there any sonic differences (ie, is the L3 sonically the same as the M3B)?

Also, has anyone with the M3B got the Gold Board for LO MC cartridges? How is it (currently, I'm using a Lyra Kleos cartridge)?

In advance, thanks for any input you can provide.