Does your tank have two return and two drains? Might consider going with two pumps one for each this way you have backup just in case. If going with just one definitely the L1 over the M1. Don't forget that they come with slip connections if you need barb connections that is an extra kit you need to order.
Yes! If I were you i WOULD GRAB THE L1.... I run the m1 ON MY 120 mixed reef and it's one of the best pumps on the market for the price. Build solid and is so quiet you can't even hear it run. Also, can only turn it up to 70% without having a hurricane in my system. I had mine now running pretty close to a year and not 1 single problem.
Ecotech M1 pump
Apex ALD Module w/ 2 Leak Detector probes
Apex PM2 Module w/ Salinity probe
Skimz 163 DC Montzer Series skimmer
Custom sump / Refuge
2 TUNZE Turbella 6055 Pumps
2 AI Hydra TwentySix HD LED Fixtures
Celestial C35W Maxspect Refuge Spotlight
Aqua UV Ultraviolet Sterilizer 25w
BRS Dual Media reactor
Eshoops IV Master & Slave Doser
Tunze 3155 Auto Top Off
BRS Per Pump 50mls/pm
Avast Kalk Reactor