alliance broadband in kolkata giving 480 kbps speed!!!!need help to clarify my doubt

hi ,

i was tried of my old bsnl connection so i thought to switch to allaince broadband does allaince broadband gives high speed Alliance Broadband Services,Internet Service Provider as it is assuring us with rs 750 plan that we can download 1 cd in 10 to 5 min!!!!need help from u guys