Practical approach to US/UK car seat issue

So I know from previous posts here that the US and UK car seat standards are different and that legally speaking a UK car seat can't be used in the US.

However ... as a practical matter, do most of you guys actually own separate US and UK car seats? Or do you just wing it and use the UK one in the US knowing that it'll be safe even if it's not strictly legal? Just curious what approach others take to this issue.

We have just bought our little one a car seat here in London (despite not owning a car!) and it seems a bit silly to buy a second one just for the odd US trip, and even to store it in London with us because not all our US trips are to the same place.

Thanks!

We used our infant seat in the US.  While I get that it's illegal, I think the biggest issue would be if in an accident, insurance wouldn't pay.  But I figured the seats are safe, regardless.

When my daughter moved up to a toddler seat, my parents picked up a cheap seat from Walmart for us to use there.  The toddler seat we have is MASSIVE and extremely expensive.  I wouldn't take it on a plane!  And we've been really impressed with the Walmart seat.  Comfy, rear or forward facing, secure, and was $40.

Also we have installed chest clips on our UK car seats as my daughter will pull her arms out otherwise, so technically we're illegal here as well.  But I'd rather be illegal and strapped in than legal and flailing about!!

Do what's right for you and your family.  You'll know if you are making the right choices or not.

We went to the states once when my kid was a toddler and went to Walmart and bought a seat .  The rental place even let us borrow a seat for free just for the trip to Walmart.  Saved us a ton versus renting one. 

Just FYI, most airlines don't count car seats in your luggage allowance so it's ok to bring.