It depends on the temperature and the person. I am a warm sleeper and I usually sleep in my Bd Suit. I have used it hunting when the outside temp was down to -10 (Was in a tent) and slept great. When it gets too warm (lows in the 30-40 range) it is too warm for me. I take out the liner or use a lighter sleeping bag. I also like the extra large bag so I can move around in the bag....I hate mummy style bags!
They are a cold weather bag for sure. Removing the liner helps in warmer weather.
I have one of the 0 degree bags and use it all year except the summer months. I have a cowboy bed roll system but run the bag instead of sheets and a blanket. Inside the bed roll is a 3 inch thick pad my sleeping bag a wool blanket and a pillow. Only time it gets taken apart is to wash and clean it . I hate getting up to feed the wood stove and this way I can out last the other guys in camp till they get cold enough to feed the fire LOL. The other cold weather camp tip I have is to camp with older guys that have to go Pee in the middle of the night or feed your buddy beer so he has to get up at least once to Pee and feed the fire .
One thing to remember about sleeping bag ratings is that the rating is almost always done with a pad under the bag to insulate from cold air when on a cot or frozen ground.
The type of camping your do will be a big factor to how well your bag preforms. The OP said a tent camp to me for a western hunt at 9000' that's a wall tent or canvas cabin tent with some type of heat source. If your planning a Coleman nylon tent take lots of extra blankets. As the summer type tents just don't hold the heat in .
I had a niece that came with us on a antelope hunt at around 8000' in Utah one fall the later part of September. She had borrowed a cot from her sister so that she didn't have to sleep on the floor of the tent that he husband had borrowed.
The first night she about froze to death. She said that it was like sleeping in a refrigerator. I told her that is exactly what she did with no pad or insulation under her on the cot. That cold air was circulation around her just like a refrigerator. She got into her dads camper where I and her dad were sleeping and took a few quilts that she placed under her sleeping bag. The next night se said that she slept as warm as toast.
So it isn't always about the sleeping bags rating.