Pick by what the brand states. Philips and Sujata state run figures. Prestige states safety features. Preethi states service. Bajaj states little. Philips gives numbers such as motor speed, run time and the working capacity of the jars. Prestige gives design points such as jar locks, leak-proof lids and an overload protector. Sujata gives motor construction, with a universal motor, double ball bearings and copper windings. Preethi gives couplers, flow breakers and service. Bajaj gives a short summary.
Look at the wattage next. Sujata is at 900. Philips, Prestige and Preethi are at 750. Bajaj is at 500.
Then compare the jar sets. Philips, Preethi, Bajaj and Sujata each list three jars on the model here. Philips lists three stainless steel jars, and Preethi adds a Flexi Lid. Sujata lists a blender dome jar, a dry grinder and a chutney jar, and Bajaj lists a wet, a dry and a chutney jar. Prestige lists four and includes a juicer jar. If juicing matters, the Iris is the only one of the five with one.
Then read the warranty lines side by side. Bajaj states one year. Philips states two years on the product. Prestige covers both product and motor for two years. Preethi gives two years on the product and five on the motor. Sujata states no term on its page. A buyer who cares about the warranty should read these lines first.
A brand name tells you little by itself, so compare models and not logos. These are five single models, and a brand may sell others with different motors and jar sets. Where one page states a figure and another does not, treat the gap as a reason to ask the seller, not as proof of weakness.
For deeper views of one brand, read the best preethi mixer grinder, best sujata mixer grinder or best philips mixer grinder guides. The best mixer grinder page compares more makers on use. The best mixer grinder 750 W page narrows to one wattage.