All string players should have at least one mute, and there are three important factors to consider. First and foremost, ease of use. How quickly can the mute be put in place or removed? How important is this to you? Orchestral players often have only mere beats to install or remove a mute. Secondly, sound quality. The goal of the mute is to lower the volume only, not dampen the good quality of your instrument. Regarding overall sound quality, the degree to which a mute "rattles" when not in use but still on the strings between the bridge and tailpiece is important as well. A heavy metal practice mute is used by many who live in apartments and offer the best dampening. Third is aesthetics. Truth be told, many players consider the importance of overall look and feel, trying a variety of mutes to discover what works and looks best on their instrument. Fortunately, mutes are not too expensive, so this is a relatively low cost endeavor.
The most common questions about rosin, concern stickiness, rosining technique, rosining frequency, and cleaning up excess rosin. A large number of rosins are commercially available varying in shape, packaging, colour, grade, special additives, and recommended instrument. Violin, viola, and cello rosins will vary in stickiness with light rosins usually providing less grab than dark rosins. Less grab is usually desirable for violinists or in high heat and humidity climates. More grab is appropriate for cellists or in low temperature and humidity locales. With double bass players using the stickiest of all. Read this great article.