My first rifle was a marlin .35 and I still use it in the Texas brush. My favorite rifle is a 7mm-08 I built. I was shooting that Marlin at 8 years old. It kicked like a mule then but I have never had to track an animal with it. I guess you could go to a range and try a few calibers too.
I've ordered from both and had good experiences with both. Boyds was a bit slow to get but it was also near the holidays. I also needed to mod the boyds a bit due to some barrel contact. It was easy work that took about 10 minutes. I would still order from either again.