Like others have already said, the TF can't be tethered when rf'ing.
I have both a TF and a Radian. I like the TF better, but I don't mind the Radian - I've had a very love/hate relationship with it over the last year though.
What kind of climate is your friend in, and will their vehicle sit outside in the cold for any long periods of time? Adjusting the harness on the Radian in the cold is one of my biggest hates. I spent 5mins after changing the harness height just getting the straps adjusted tight enough.
Pro's of the Radian:
- Taller top slots than the TF
- Can be tethered rf'ing (if that matters to your friend, I personally don't find it to be a selling point, but others have different opinions.)
- Has a low profile, and deep seating area, so older kids have more leg space when rf'ing. It also looks more like a "big kid" seat when used ff'ing
- 8 yr expiry
- folds for storage, fits well on an airplane
Cons of the Radian:
- Difficult to install in some vehicles - there's a definite learning curve and it can be pretty huge in some vehicles.
- Harness hard to adjust in the deep cold (-20 celcius or so it's super hard, but down below freezing it just gets harder and harder.)
- Difficult to install more upright than 45* depending on the vehicle. Conversely, in some vehicles it's near impossible to get the 45* recline a newborn needs.
- Some kids find the harness rubs on their necks.
- Seat is quite upright when ff'ing and many kids have severe head slump in the seat when they fall asleep. Some kids find it more bothersome than others.
Pros for the TF:
- Tall shell, highest of all available seats for rf'ing.
- Seating area is very deep and also has plenty of room for legs when rf'ing even with an older child.
- Seating area is wide so broader kids will have lots of room in it.
- Loads of EPP foam and a very deep shell.
- Seat is side impact tested.
- Has built in lock-offs
- Harness is easier to adjust in warm weather than the Radian, but I don't have any cold weather experience with it yet.
- Seat has a natural recline when ff'ing similar to the MA and the deep side wings are great for resting a head against.
- Harness doesn't have to be re-threaded when changing harness height, you just pull two yellow knobs on either side of the seat and slide the harness to the proper height.
- Removable headrest for rf'ing children under 22lbs and whose heads are below the red line on the seat cover. Fits better in small vehicles if you need to use it with a young baby.
- Easier to adjust the rf'ing recline on than the Radian and takes up less room than the Radian when rf'ing even with the headrest on.
- Cover is more padded than the Radian.
Cons:
- Harness adjuster lever & strap are low - when seat is installed rf'ing and more upright, it can be difficult to access depending on the contouring of the vehicle seat.
- Lock-offs have to be used. Some people have had difficulty using the lock-offs.
- Harness is a continuous loop which some people really don't like.
- Buckle tongues are slightly narrower than the harness straps, this is once again a personal preference thing.
- The natural recline of the seat when installed ff'ing is a con for some people who like a more upright install.
- Top harness height in actual use is a little lower than the Radian. It's still tall enough to get most kids to a safe size and age for booster use though.
- It's a fairly wide seat and likely wouldn't work in 3 across situations. 2 seats in the same row will work with almost any seat though and I'm sure this is no different.
Her best bet is really to try both seats in her vehicle, play with each to see how she likes the harness adjustments, and see how her kiddo fits in the seats before making any kind of decision.
I love the fit of my dd in the Radian, but hate the frustration I sometimes have tightening the straps and installing the darn thing. She also has terrible head slump in the Radian when she sleeps and it bothers her enough she often wakes up repeatedly until she's so tired she can't keep her eyes open.
The TF the continuous loop sometimes annoys me, and the fact that I can't get it more upright in my truck due to seat contouring bugs me a bit, but dd loves the seat and sleeps well in it. She also fits very well in the TF - no cramping in the shoulder area at all which is a complaint in the MA. Given the choice, she likes it better than the Radian, and I do too.
(I still like my EFTA better though.
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