The Ola cab experience that I had till now has been plesent. There one once situation where the driver refused to pick me up, because of the peak hour traffic and the distance between me an him. But somehow convinced him to pick me. This was caused due to their shortage of cabs and the driver was not to be blamed as it was a genuine reason.
So once more cabs are available during peak times, the Ola service will automatically be better.
BTW, I had booked Prime for most of my rides and the cabs were realy good.