We used the Fast Stash for many years until the zipper broke and that was also not freestanding. I really liked that tent.
There are times when you can't get a tent peg into the ground. In those cases, you need to grab a rock or a log. It's not as convenient as a freestanding tent but it never caused me too much grief. Bring a little extra string in case you need to make a longer run.
One issue with the Fast Stash is that is used your hiking poles as the poles so you needed to make it flat each day. If you weren't careful, you could get into trouble in a rainstorm.
I haven't used the Carbon Reflex 2 so I can't speak to how much force the pegs need to hold for that tent. Less is better obviously.
Edit: I should add that when the Fast Stash broke, we replaced it with the BIG AGNES FLY CREEK HV PLATINUM 2 TENT this past summer and we've been happy with that tent and I'm not complaining about never having to worry about pegging it down anymore.
Last edited by Steventy; 10-21-2017 at 07:27 PM.