Simple question, for I’m a bit unenlightened on the subject:

Can I use differing rotor and calliper brands? Namely Hope 4 bolt 180mm Rotor with a Magura calliper? My current wheels are 6 bolt SRAM hubs, and I’ve the chance of a pair of wheels with Hope 4 bolt hubs, all 180mm variety.

Or will it all end in tears and spilt blood.

No it’s fine. I’ve not used the same brand rotors for years and I’m currently alive.

Hope with Hayes, Hope with eBay cheapies, shimano with superstar, shimano with avid etc….

Not dead.

Glad to hear that no bad thing has happened to you Kayak. Will pursue the purchase with vigour.

only issue I have had was with Shimano a few years back and hope floating rotors and the rivets catching the mount, 5 mins with a file fixed it. I think the newer ones have more clearance.

Hope are well fat so might not fit!