How did it look and feel?
Putting it on, as expected my waist appeared an inch or two narrower. You can adjust it, to cinch in your waist to your desired tightness. I kept it on the loosest notch, mainly because I wanted to be able to breath comfortably. If you've ever worn a pair of spanks before, it has a similar effect to that, only this time you get more of a curvaceous, hour glass look.
The lining is cotton so the material is soft on the skin and style-wise it looks really nice even on the outside of your clothes. It also sits discreetly underneath a t-shirt or vest so no one would know it was there. Top secret!
Can you exercise in one?
Well, I wanted to road test the waist trainer with a mixture of workouts so I wore mine in a spin class where I'm mainly sedentary on a bike and a body pump class where I'm bouncing about the place and using weights for added resistance. In the spin class I found I had to lean forward further than I normally would and found my breathing was inhibited slightly. I wouldn't describe it as uncomfortable, but I did feel quite restricted. It takes some getting used to.
As for the body pump, I had a few niggles. I found that when I wanted to engage my core during exercises such as lunges, squats and sit ups, those muscles around my core had switched off or disengaged because they were being squeezed meaning I wasn't able to properly work them out. As someone who is qualified in personal training, I would only advise really light exercise whilst wearing a waist clincher, specifically, brisk walking.