It's informal and often used in casual conversation, not in formal settings. You should've seen him at the race, his car went like a bomb!
Pro Tip 2/3
British Origin
It's a British phrase - English learners should be aware that it might not be understood everywhere. I heard that in the UK, the latest Harry Potter book is going like a bomb.
Pro Tip 3/3
Positive Excitement
The phrase often conveys excitement or admiration for something being done really well. Her performance went like a bomb - the audience was thrilled!