So... I'm 46, 5'6", 72kg, usually an AU size 14. With my measurements at B 101 (14C bra), W 88, H 108 - I fell right in the middle of the Large range in the size guide, so this is what I purchased. I would say that this was definitely the right size for me. Tight, but of course that's how it should be.
So, here's my thoughts - fantastic product that does exactly what I had hoped. If you expect it to work some kind of miracle, you will likely be disappointed. It's not going to magically reduce your weight by 20 kgs the moment you shimmy into it. Or reduce your dress size from 14-16 to 8-10. But if you're realistic in your expectations, you will definitely be pleased by what it DOES do!
For those of us who aren't fortunate in having our fat evenly distributed, instead having fat deposited in lumps and bumps - it definitely does help to smooth those out.
As another reviewer said - I am able to wear outfits that have long been shelved - simply because that smoothing effect has made me feel that I look a lot better in them! I wouldn't say that an outfit that didn't actually fit you, would fit with the shapewear. But an outfit that did fit, will fit better and look nicer, for sure! And you'll FEEL better in it - more confident! And that is what it's all about imo.
Bottom line - it smoothens, firms and reduces the jiggle of lumpy fat deposits and aging.
Getting into it is a bit of a challenge, but worth it. Probably not great for someone who has any kind of joint issues in their arms or shoulders, because it does take a bit of muscle! The wee opening is doable, just takes a bit of concentration and care. But may not be so easy for someone super curvaceous.
One thing I wish was improved is the way the back fat bulges out of the top of the body suit around the back of the underarm area... which you can see from the videos. Maybe a higher cut would help? But that certainly wouldn't stop me from wearing it!
Overall - love it! Very pleased with the results :)