Hi Simon, We've used quite a few DAC SFP+ cables of various length, and it seems that regardless who you order from (4 vendors so far) you end up with some giving a small degree of CRC errors - I think we have had to order about 1.15x as many as we actually want to use to get a set that work.
For anything 5m or longer it's really not much cheaper than a pair of MM 10G SFP+ from flexoptix (or others I'm sure) plus a patch cable. -- Peter Taphouse Bytemark Hosting http://www.bytemark.co.uk/ tel. +44 (0) 1904 890 890
