Ion Radar and Sonar 2021

[Lucio82]

Hi Guys!
I would like to buy a seat harness and i think the choice will fall on a harmess Ion, between two harnesses that appear very similar to each other: Ion Radar e Ion Sonar 2021.
What are the main differences? Clearly both have a CURV plate for even more overall comfort and better load distribution. But looking at photos, it seems to me that the Radar has more padding on the inside and is a little taller. Am I wrong? I also noticed that the Sonar has a fourth buckle above the thigh hooks. Maybe it is tied to the bar to keep it firmly anchored. But i don't know.

I'm also interested to know which size is the right choice about a seat harness. My waist is 86 cm and according to the size chart I I should choose the L but I am at the limit between M or L.
Does anyone use an Ion trapeze like Sonar or Radar? Is it possible that after a certain period of time the tissue expands slightly?

Thanks

[LePhasme]

I have the ion radar 2021, one of the local shop told me they are both very similar except the sonar is more for foiling (but you could also use it with a TT without issue).
That being said, I had the 2020 radar and the lower straps of the webbing both seriously deteriorated in about 8 months, luckily ion agreed to refund the harness under warranty and I used the money to buy the 2021 version, except after about 6 months I can see the right lower strap is deteriorating again.
I would advise to buy it from one of your local shop as it can make it a lot easier to use the warranty and would allow you to try it on to find the best size.