Both types of ice protection work well in my experience. But each has shortcomings.
The TKS system installed on the Hawker series requires constant use and testing to maintain readiness. It also does little good if it's not activated before icing conditions are encountered. In short, it takes knowledge and discipline on the part of both mx and pilots to be effective. The juice must be flowing a couple minutes prior to icing in order to provide proper anti-icing protection.
The pneumatic boot systems installed on numerous airplane types I'm familiar with also works well within it's limitations. The boots must be kept clean and damage free in order to work as expected. Several surface treatment options are available to enhance boot serviceability. Pilots must be knowledgeable and disciplined with regard to their limitations and use on the specific airplane type in order to use them safely. In spite of the information certain safety regulators may promulgate, not all boot systems and airplane types are the same when it comes to using boots effectively.
Both pneumatic de-icer boot and TKS anti-ice systems are effective within their limitations if properly used and maintained. They have also both been misused or ill-maintained and been factors in icing related accidents. The heated wing concept is superior in both regards, but requires a considerable supply of hot air or electrical power that many airplane types are by their design, not equipped to provide.
I personally find the boots to be marginally superior to the TKS system because the boots are used after icing is detected. Since TKS must be used before icing is detected, then it must be activated anytime icing conditions might be encountered. With a limited quantity of fluid available and the possibility of entering unanticipated icing conditions, I'm just a little more comfortable with the boots. Heated surfaces would be my top choice if choices were offered. Knowing the limitations and proper usage of whichever ice protection systems the airplane being flown has installed is the most important factor in determining it's effectiveness in providing protection in icing conditions.
The best use of ice is for chilling your cold beverages!