It is hard to find statistics on how much consumers like or dislike responsive layouts. They don't care much about the technology involved. For them, experience is the only thing that matters. RESS is an approach, one of many, that may help in providing great experiences across devices. Of course it is important to provide this experience, instead of failing before we provide anything or providing unusable content. Whenever conversion of an existing website to responsive layout is considered, we need to understand the limitations and, when possible, overcome them with the use of Server Side components and JavaScript.
After we are able to provide the user experiences we intended with our design, the benefits are obvious, which are as follows:
On big screens, the web page finally uses the whole possible area, which enables a more engaging experience.
On small screens, readability is guaranteed.
Lowering costs of "going mobile" for website owners means that users will get more websites optimized for devices than it would be possible without RWD.
Bandwidth issues can be solved with RESS.
In many scenarios native applications or mobile websites can provide better a user experience, but before resigning from responsive solutions some questions should be asked such as, does this advantage justify the difference in the cost of development and maintaining separate versions of the website? Is our device detection kit really as reliable as we'd like to believe? And how future proof will this solution be? Borders between device classes (used to determine templates to device relations) are blurry and will fade even more with time.
Note
Future proof is a buzzword often used by the RWD community as a selling point for RWD: www.techopedia.com states; in reality, very few things are truly future proof and that is the sad truth about all web things. RWD probably will be more future proof than native applications; the future will tell us. Nonetheless, it will be definitely cheaper to maintain RWD/RESS websites than native applications.