Squash Strings
Squash strings are probably the third most important part of your squash kit, although many pros may consider them almost as important as the racket. In the past, the tendency was to provide poor quality nylon strings at much too high a tension which played badly and lasted ages. Some manufacturers now supply rackets prestrung with good strings, notably Harrow and Black Knight which are prestrung with Ashaway; and Technifibre which are mainly strung either with 305 green or X-One Biphase. Higher-end Prince rackets also use good quality Super Syngut 17 strings.
However, a prestrung racket may not give you the gauge of string you require and different rackets will tend to be strung to the same tension, regardless of headsize, which is not ideal. It is well worth experimenting with a few different strings to find one that suits you. It will make a big difference when you do. After choosing your squash strings, check the racket product listings for recommended stringing tensions for each racket. You can then take this as a starting point to finding a string/tension combination that works best for you with a given squash racket.