I think the thought around the explore bonus is that you use it for batch explores. I'm surprised no one has mentioned this yet, but I'll bring it up just in case it's not known.

You can only use it 3 times, and because of the way batch exploring works, if you use it to start the batch explore, you will get that explore rate for the whole batch.

So if your base rate is 40a and you use the 10% bonus and do a batch explore of 120 turns, your base will be 44a for all 120 turns. That would be a ~500a bonus. That is certainly worthwhile, IMO. We limited it to 3 uses because it's pretty powerful when used in a batch exploring context.