What should I prepare for: IAS or IES?

You should prepare for IES. This will be a shock to you since most people will suggest the same. Here’s why –

• It is easier to qualify for IES when compared to IAS. There’s more chance of qualifying it even in the first attempt. Whereas, there are many students who are brilliant and hardworking that aren’t able to qualify for IAS. It requires more patience.
• IES syllabus is very close to the engineering syllabus, making it easier to grasp and understand.
• You don’t need to have excellent writing skills or sharp memory to have an edge over other competitors.
• Even if you fail in IES, there still will be an option to give GATE and get into PSUs. With IAS, there is no backup plan if you fail to qualify.
• When you are preparing for IES you are basically preparing an optional subject for IAS as well. So in future, if you want to prepare for IAS you will have an optional subject ready along with a job.

You have a choice between good with a high probability of selection and better with a low probability of selection. So going for the option that has the maximum probability of selection along with a backup plan in case of a failure is a better choice.