I have installed a Panasonic UJ-240 in my W520, it works like a charm.
Me, too... mine's a bit of a hack job because I trimmed the original faceplate with a utility knife instead of stealing my W520 DVD's faceplate. I did "borrow" the back and side guide pieces. The Lenovo DVD drive still works okay without them... I keep using it when I don't need Blu-Ray because I've had drives fail often enough that I want to see if I can use this one up under warranty.
Would be nice to be able to get extras of those plastic bits. Maybe I'll post a WTB for a dead optical on the appropriate forum.
W520 (2820QM, Q2000M, FHD, mSATA SSD, dock)Previous: T61p (died 1m past warranty ), Dell 8600, iBook ("Dual USB"), Gateway Millennium, Macintosh G4 , PowerPC Mac clone, Mac Duo 210, iBook (clamshell), Quadra 630, Mac IIsi, C-128, C-64, Vic-20