- How deep is the project?
- What is the rock?
- Is it hard, soft or complex rock?
- Is the rock very complete, semi-broken or broken?
- How is the abrasiveness of rock?
- Have you use any other brand before? what is the brand(optional)?
- How is the performance previously?

such as:

→ drilling speed?
→ meters downhole?
→ drill bit working life?
Above questions will help us be more familar with your ground situation, meantime, more accurate and appropriate bit will be provided to you.