Question

When listening to different tapes of the Qur'an I noticed that some reciters read more slowly than others.  Can we recite at any speed?

Answer

Yes and no.  If you can observe all the rules, recite each letter from its proper articulation point without making the letters unclear or garbled, you can recite at any speed that is feasible for you.  A big word of caution: Only those who have studied Qur’an extensively under a qualified teacher are able to read quickly and accurately. 
A second word of caution: In a class situation, you will be expected to recite slowly and clearly, so the teacher can listen and correct mistakes as much as he/she is able.  This means that if you are accomplished enough to recite accurately while reciting quickly, it should be done a situation other than the classroom.