We have a Samsung one, it was the best power available for the cost and doesn’t look like a Transformer knock-off toy from the 80s. Plenty powerful enough, and pretty well thought out.
We previously had a Dyson cylinder which of course was a lot more powerful but I don’t think it got the house any cleaner. And because our house is all stairs it was a massive ball-ache to use, so we now hoover much more frequently.
Dyson and Shark both seem woefully underpowered.
Question is – how much suction do you actually need? You’re not sucking the dirt out of the carpet, you’re brushing it out and then sucking up the now airborne dirt. I’ve not noticed any change in the cleanliness of the carpet since going to a handheld one except that we clean more frequently and more easily.