Both are excellant and both are super at 1k. Lot of records set with both.
The weatherby would be my choice IF you order a min SAAMI reamer with appropriate freebore for your bullet. The weatherby has a definite advantage with the 240 SMKs. Factory chambered rifle, go with the Win Mag.
No issue reloading either of the two and barrel life is exactly the same with same reloads. Both require dies to be set to headspace off the shoulder. Both will go 1000-1400 rds top gilt edge accuracy.
Excellant brass for both with the RWS (best brass available) available for you in Europe which is easier and cheaper to buy there. Again gives the advantage to the Weatherby.
I have reloaded and shot both competitively and will take the Weatherby hands down.
BH