Whereas most archers get a free low-damage, rapid-shooting bow, but can spend money to get something more powerful (albeit slower), the Sarranid archer gets a free low-damage, rapid-shooting bow (the same one received by Khergits and Vaegirs), but can upgrade to even even lower damage, even faster-shooting bow (the same one received for free by the Nords). Worth it? Hard to say. Generally, Sarranid archers are the most cheaply-equipped class in the game, ahd Sarranids who do well will rapidly run out of things to spend their money on. (Even faster than archers in general, who are typically the most cheaply-equipped of the three classes.)