We loved our popup, we had it for 9 years, and spent 2 weeks in it every year, but numerous weekends. It was a 12ft box, and we slept 8 in it one weekend, and 5-6 regularly. Is it cramped? a little, but it's camping. We swapped to a TT because the kids are teenagers and didn't want to share a bed, and we started taking my MIL, and SIL regularly, and they don't know the meaning of packing lite. :)
I will say to keep an eye out for a good used one. We found ours it was 3 years old, and was garage kept, and used 3 times. We got it for about 60% of the cost of a new one. We continued to garage it, and washed the canvas after probably 75% of the trips, and never put it up wet. It was 12 years old when we sold it, and sold it for $1000 less than we paid for it, in 24 hrs. Probably could have sold it for what we paid for it.
We loved the pup, and would not be against another one.