long lament - seeing a car seat makes me want to cry

I have spent virtually every waking moment (and some sleeping moments too ) of the last three months thinking about, reading about, looking at, and trying car seats. It seems there's no perfect one, especially for the grandparents' car. For ODS, who just moved out of our RA (he's 3 yrs, 36 lbs, 41 in, and i think a 14 in torso although it seems to vary by day, or at least by the seat), here's the rundown:
MA - he was at the top slot with a sweater, but I think I can move him down.
Don't love the adjuster, but I'm learning to be ok with it. Easy for GP to install, but not sure the harness will get tightened sufficiently. I was ready to sell this, but yesterday (his first ride in the Ma in a long time) he fell asleep in it and he looked comfortable, head gently off to the side. So now I think maybe it's the most comfortable for him?
GN - easy to install, easy to adjust, but heavy, especially for GP, who moves the seat in and out. ODS says he likes the cupholders, doesn't look too comfy when he sleeps.
Radian - couldn't get a good install, so sent it back
TF - not sure about the harness adjuster, especially for GP. but sure is easy to install, ff at least, and ODS looks comfy and well protected. It's my first day using it.

So we have a RA, MA, GN and TF for our 2 sons (yds is 1 yr, 23 lbs, 31").
clearly YDS gets the RA. Now I need to decide where the other seats go (at least one for GP, one for main vehicle, one for spare vehicle). I can get a solid install for all of them. I can't talk to DH because he just tunes me out
I am going around and around, which probably means it doesn't matter. I guess I'll keep trying them until I can get a good handle on what I like, what DS likes, and what GP can easily use correctly.
I'm sorry, I just needed to unload, there's no one here I can talk to anymore,
they all think I'm nuts
How do you all stop thinking about this? Or do you?

Hang in there...it's tough to figure this stuff out for anybody. I don't think you're going to go wrong with choosing any of the seats. We have an MA in my parents car and my dad even knows how to put it in and take out (and was always my helping hand as I was learning) and I have found the straps to be very easy to adjust and never noticed my parents having any problems with it either (SUPER great install if they have latch!). I can't speak to the true fit or nautilus (don't have one - although dh is picking up the nautilus to try today!). I am really leaning towards nautilus for next seat for grandparent's vehicles because I have heard it is easy to install...it will harness her as long as she needs it...and then turn to a booster so that is all they will need. Good luck...wish I could help more. Just make sure that whatever seat you choose you show them how to correctly operate (a few times...gently of course). For the first two years I always checked grandparent's install or helped out until I was comfortable with their install. Good luck!

Okay...duh...I was just thinking of another reason the graco would be superb for grandparent's vehicle. You will not have to teach them how to use anymore seats after this (except when you convert it from harness to booster). That would be a big bonus IMO. If you went with MA or TF and choose to harness pass those seats you are going to have to teach them a whole new install and securing child and such. Might be something to think about.

Thank you for your support. I realize I am lucky to have the luxury to try all these seats, and that in reality they all work reasonably well. It's just that once you start down the road looking for "the one" it's hard to quit until you find it.
My parents have actually done quiet well with the RA install, which makes me think the MA may be a good choice for them. And it's lighter than the GN. But I think the GN may be easier for them to use (although the chest clip and buckle are a little hard). I'm thinking the GN for them simply because then I wont have to go through this again so publicly with them
I'm kind of liking the TF after my first full day with it, but need to see how ODS dos in it. Although in all honesty, he doesn't much care.
So we'll switch things around as much as my LO can bear to humor me, and by then he should have outgrown everything (DH is 6'4" and both boys show every sign of following in his footsteps) and we'll have to start again. Hopefully there will be more/better options in a year or two.
Meanwhile, has anyone else noticed that their child seems to be different sizes in different seats? Or even he same seat on different days? Why is harness height not a constant?

Yes, we are blessed to have these dilemmas.

I don't have as much problem with harness height...although I am sure dd was at the right slot before I installed the frontier and now it's like she's one down too far. ugh...

I have not tried a TF or RA yet so can't comment on those. I did find the buckles on the GN a little difficult too (and hadn't heard anyone else mention that until now).