I am assuming that you are referring to Xolair! I was too allergic to be able to have them. Have a couple of friends that did it, their Asthma is no better, but that is not to say that you will not benefit. You are more likely to find a larger group of Asthma Sufferers who have tried this treatment on Asthma UK. I recommend that you join their forum and ask, there you will get a wider range of responses and support.
My personal thoughts though are if the main drawback for you is having them every two weeks and to be kept in hospital for a couple of hours afterwards, isn't it worth a go to find out if it works, a small amount of inconvenience, for what could be a huge improvement in life quality.
Good luck Daxiemad