The main difference between the Euroflex M2R and M4S is the steam temperature, PSI, and accessories. The Euroflex M4S provides slightly hotter steam up to 275⁰F, while the M2R offers up to 266⁰F. The Euroflex M4S delivers a higher pressure of 40 PSI, while the Euroflex M2R offers up to 36 PSI. The M4S includes all the accessories for above floor cleaning, whereas the M2R is a steam mop only. In terms of performance, the Euroflex M4S is more versatile. As a result, it is slightly more expensive than the Euroflex MR2 steam mop.