[Grzesio]

Basically - shorter fuselage gives less drag and a lighter airframe (no need for carrying weight of a long fuselage needed for supporting the tailplane), it may be also necessary due to certain design features (e.g. necessity of placing an engine close to the centre of gravity).

These advantages are however partially neutralized by additional means of stabilizing a tailless a/c in flight. In the pre-fly-by-wire era this could be achieved by using a selfstabilizing wing profile (with a trailing edge bent upwards), which could stabilize even a straight winged tailless a/c, or a sweptback wings with twisted wingtips (with negative angle of attack, what was far more popular than selfstabilizing profile and actually used in Me 163 - what is easily seen in side views of the Komet) - such a wing has naturally more drag than an usual wing. There's also a problem with stabilizing momentum, as it varies with varying speed - basically a tailles aircraft is stable only in particular speed, when it is flying faster, it tends to lift its nose up (i.e. to climb), when it is flying slower, it tends to dive - this has to be constantly controlled by a pilot with an elevator or special trim flaps (in case of Komet these trim flaps were really big - what you can see on the inner trailing edges are trim not landing flaps). There can be also a problem with poor directional stability due to small momentum produced by the fin, placed on a short fuselage.
But generally a well designed tailless aircraft (such as the Komet) are light, powerful and stable in flight. For example the Me 163 diving with no power (after burning all the fuel) was faster than any Allied fighter trying to chase it.

Regards

Grzesiu