Not compatible with methanol/diesel/oils. No information on maximum flow rates that I can find, Id question whether it could potentially become a bottle neck at some point, I guess that's why some are available with multiple outlets? Also the return line should be mounted above the pickup no more than one inch away, so obviously the wick is a restriction and the best flow is achieved near the pickup, meaning the flow is potentially different across the mat depending where the fuel has sloshed to. Thinking about it more though it really shouldn't matter if the return line is correctly located.