I've used the FK Tarp for a 2 month trip, in which I slept with the Tarp up for the majority of days, so I may have a unique perspective, until more people get to utilize it - some pluses:
This tarp is very large! It's large enough to fit two people in, comfortably, so when thinking of pack weight, remember you can half your gear load weight if you share this with your partner: perhaps one person could take the tarp, and someone else can take the stakes. Using it solo was quite the luxury, as ALL my gear could fit underneath the tent easily, and I could certainly spread out, myself. It would take a little bit of practice to learn how to put up the tent alone, but it's certainly doable.
No problems with it handling any of the weather I encountered: all-night rain, thunderstorms out of the blue, snow showers, wind - all the above in the span of 8 hours, etc. I used this tent at 12,000'+ without wanting anything more. I believe the open air designs helps keep condensation down, which helps with packing up in the morning - less need to have to let things dry out while breaking camp down.
Light! This tarp is a very light piece of gear. It's entirely realistic to bring it along, even if you don't know you'll 100% need it. You could play around with bringing the tent alone, and attaching the guylines to tree branches, or just use it to wrap up your sleeping bag in (to gain a little bit of warmth) but both are obv. not how this piece of gear is designed. I have been in a situation where it was 100% imperative I get out of bad weather immediately, and made due with hanging out underneath the tarp, with only my trekking poles up to hold the tarp above me. One the weather got a little less severe, I could then put up the entire tarp correctly. If you're a pro, you could potentially put up the tarp while being entirely underneath the tarp (and dry), staking it as you go. This would look very funny to anyone watching you, but I guess you're not dripping wet/cold, so you'll have the last laugh!
Fast! This tarp is fast to put up and take down. I would invest in some time to wrap and tie each guyline separately, so you don't come back to a tangled mess.
Rain Protection! Even with the open design, I never had a problem getting soaked at night. You may want to strategize a tiny bit and think about which way weather may come, and put the foot-side in that direction, but if you don't, you'll still be fine. I never crossed the poles to make a lower profile, but that's another option!
Overall, I think you'd be very happy with the FK Tarp. I moved to the FK Tarp from a more rectangular tarp design, which didn't have one way to set things up. I thought the flexibility would come in handy, but in reality, I just never ever got a great tarp setup, just an, "OK" one. With the FK Tarp, every time you set it up, it's set up perfectly.
I look forward to many more adventures with my FK Tarp! It shows little sign of stopping.