Holy Grail ERF seat for travel

[RoseValleyRambles]

We need an erf seat for our 2yo (13kg, 82cm so slightly smaller than average). It needs to be usable in a taxi/Uber, and then install/move easily between grandparents cars. It will be occasional use so I don't want to break the bank.
Taxi bit seems to be the deal-breaker. We're looking at:
Joie every stages as an erf until 18kg as it's belt fitted. Would probably then get a safer ff seat as I don't think it performs as well as others.
Axkid move (but worried about tethers in a taxi scenario).
Beyond the other axkid models, is there anything else we should be looking at? Have any other erf parents found a good solution?

We used to take our current seat, pad it out with bubble wrap and into a car seat bag or the original box. We hired a car though, so this might be more challenging with taxis.
I’ve heard great things about the TinySeats Two. ERF upto 125cm (23kg) then converts into a booster upto 135cm. It folds up for easy travel. It’s isofix, but I guess if you’re booking a taxi you could request one with isofix. It’s also pricey (£485 😬)
Stages would be a good option though, especially if your little one is low centiles.

Tinyseats is probably the holy grail as it can RF up to 125cm and it's very quick and easy to fit, but it is pricey as said!

I would look at Graco Extend R129. It also only goes up to 18kg but that won't matter as your LO is on the smaller side. Actually the Joie Every Stage R129/Graco Slimfit R129 recently got a decent score on ADAC - better than the old Every Stage anyway.

I don't think an 18kg limit will be a problem for you, TBH. So I would forget 125cm limit seats and tethers - this just seems to be creating a problem which you don't have.

Halfords actually even have an extremely cheap own brand seat which rear faces up to 105cm/18kg. I don't know what to make of it because it looks so flimsy, but it's certified up to the weight limit, and in theory, it doesn't matter how basic your RF seat is as long as it is rear facing, because it's the rear facing which makes it safe.

Really useful. Thank you! Your comment about rear facing helps. The adac scores for Graco/Joie for a front impact crash worry me a little, but am I right in thinking they treat it as a front facing seat for those given it can work both ways @BertieBotts ?

Which one are you looking at? The Every Stage R129 or the older one? The R129 versions don't have a forward facing harnessed mode - they are just rear facing + high back booster.

When a seat has multiple modes, they take the scores in all the modes and they average them. Which is why purely rear facing seats score better than 360 spin seats, and 360 spin seats score better than purely forward facing ones.

It won't perform as well as a seat with a support leg, because it's reclined and a seatbelt doesn't support as well as a leg.

@BertieBotts the r129. I think we're settled on that, unless you know of anything with the combo of belt and support leg, no isofix or tethers.

I believe the only seats that do that are limited to 13kg rear facing, and they tend to be the sketchy brands you only ever see on discount sites. Cosatto also have one (again only 13kg RF when belted) but Cosatto haven't done very well previously on the ADAC test either.