Either Slayer. I have several mags including two 7mms. But in all honesty I think a .270 WSM loaded with the right bullet is as close to "the perfect" North American round as you are likely to find. I am absolutely smitten with the Kimber Montana in this caliber. It certainly will find its way into my safe, likewise for the Sako FinnLight.

BTW if you just cant decide, Sako is picking up the 7WSM for 05 in their rifles. That way you will have the best of BOTH worlds from the calibers you asked.
RA