I have had a few sets of brakes like these, Paul's, prg, onza, rbp etc. They do the job of stopping, but are inherently different to set up as they have the spring tensioner as part of the brake rather than using the stops on a frame or fork. This does make that aspect more of a faff to set up over standard brakes for sure, and more tools required for a simple job.
However I'd say there are some bonus aspects.
1. Pad set up is easier
2. Pad height adjustment range is greater so can be adapted for wheel sizes
3. Can switch cable clamp side over to support cable runs
4. Look very nice
My Paul's look and work great, a change from the norm, but not without compromise. The levers had play from new, I do have to retention the brake bolts periodically (though I think that was down to me using alloy bolts that stretched and finally snapped one day).
Avid ultimates are the best v brake I've got on a build, they do everything needed, can swap cable clamp side with ease, levers are great. Arguably more expensive than Paul's, but better.
Standard brakes like avids and Shimano do the same job, just in a quietly generic looking way, nothing wrong with that either.