What blender is required to create an emulsion? Let's consider for specificity an emulsion prepared with the use of a protein possessing emulsifying properties as an emulsifying agent. Domestically most commonly prepared protein-based emulsion is mayonnaise.
Recently Cook's Illustrated has complicated matters by reporting that at least one of the blenders they tested using a tachometer has the blade rotating at a speed, which does not correspond to the specified by the manufacturer. It looks like these findings were not replicated by other teams. Defects are not uncommon in production of household appliances, but if it is not a problem to measure temperature within an electric oven using a thermometer, measuring speed of rotation is not as easy since a tachometer also has to be tested for accuracy of performance. Yet the speed of rotation is a critical determinant of emulsification efficiency. What also is of interest is that manufacturers like KitchenAid (probably the second most highly rated brand after Vitamix) do not specify the speed of rotation of their blenders’ blade, so a blender suitable as an emulsification device can be five times less expensive than renowned for high speed alternatives if it meets minimum speed and power requirements.
So I would like to know whether anyone here has experience of using different blenders for emulsification and does not mind to share it with others.
An emulsion, like mayonnaise, can be made with a fork, a hand whisk, an electric whisk, a stick blender, or a traditional blender with a jar. I've made mayo, at some point or another, with just about all of these.  For home use, the hand whisk is often the most convenient if you are handy with the technique.  However, I find a stick blender to be the best option, for speed and easy cleanup.  One caveat is that the container you are making the mayo in should be just slightly larger than the blade end of the stick blender.  For me, a cocktail shaker is perfect.