It is like cables. I used to like the very bendy cables from Van Damme, they came in colours and didn't tangle. However I had the core break in two separate cables. As I have started making cables for people my main concern is reliability and of course a wireless system and a cable do the same job. It is more hassle that it's worth to chance it with a cable so the same should go for a wireless system.
In my former life I used many wireless systems and the professional ones from the big names all worked well under the most. arduous conditions. One day we had a problem at an exhibition with a mic working in the free band. We had to borrow a mic from one of the major brands that were also at the show. Wehad the same problem. All the free bands were swamped.
These days the free bands are mainly 863-865MHz FM and 2.4GHz Spread Sectrum. Digital TV and 4G interfere with the FM bands and wifi/bluetooth can smother the 2.4GHz band.
Most recently, our guitarist bought one of the early Amoon systems as he was so impressed with my Smoothound. AS soon as he switched it on the Behringer Air mixer we used dropped wifi contact to the devices controlling it. Now the Behringer is very sensitive and most people use it wired with a router, but it never skipped a beat with my Smoothound. Of course if you are using a different mixer there should be no problem BUT there might be. So cheap may work for you but keep a cable handy just in case.
As for the Smoothound? It works for me, has never dropped out in use as it constantly searches for the clearest channel. The reciever sits on my pedal board so I can immediately see if there are any problems. Of course in a touring situation things are different.
The down sides? Max of four per stage, battery cover is a little flimsy but in all the correspondance I have had with them they have given exceptional service.