Surround and Center Channel for Dali Suite 2.8?

This is my first post on this forum and I have to say a big thank you to everyone contributing to this site. There's a wealth of information on this site!

I was hoping you could help...

I'm just starting research on what surround and center channel speakers I should get for my existing setup, which is a pair of Dali Suite 2.8 and Onkyo TX-SR607 amp. I need to find something that has the same tone or blends in well with the main speakers I reckon? Or is it safe to assume that as long as the speakers are of good quality, they will sound well together?

What's your experience?

Many thanks

Lavend