If you use the Cisco utility to search for transceiver compatibility on a router/switch model with SFP+ ports, it WILL list the -LRM part twice.
XcverProdID Reach Media
SFP-10G-LRM 220m MMF
SFP-10G-LRM 300m SMF
But the question that interests me is OK to have a -LRM transceiver at one end and a -LR at the other end; or is such a mix heresy because the OFDM symbols wouldn't match?