Are you crazy? You have been in the UK only for a year and thinking of clearing the test now? I see you are very much aware of the test and hence requirements for ILR. As you can see the Home office have moved goal posts in the past e.g. ILR after 5 years instead of 4 years & test for ILR which was for citizenship. Who knows what will happen in 4 years. Why waste time and money. I would suggest you wait nearer the time of your ILR to give the test then.