re the cost i suppose when you compare to subscriptions most have been paying for a year, then it is expensive and would seem even more so when you find nothing:(
BUT compare a census result to a certificate most have paid £7 for you pay and wait a week, this way the result is instant,
and with the 1911 you have information on the whole family, as ive said if your not sure what your looking for then maybe best to wait, and as someone says above, in most cases this info has been there for a 100 years, so another few months they are not going anywhere;)