Every operator is providing 3.5G except some operators like Airtel, Vodafone who are providing 3.75G in cities.
Speed of a network depends on multiple factors like Bandwidth, number of users online, Network and network range. Bandwidth and Network being constant for all operators in 3G the speed depends on number of users using ur services. Cheaper price means more users using and hence low speeds. Im not considering range here. The reduction of validity of Rs 68 pack is to increase quality of service as many users will opt out of this pack and will opt for higher validity packs with low data usage. This reduces load on network hence better speeds.
