I hereby congratulate the authors on a very informative article. The topic of the mouse revisited is timely, I agree that it can benefit tremendously from new developments, but that the concept must move closer to the application, and should become easier to use by non-NMR/MRI experts. The article is written in a very readable and entertaining manner, and yet is of high technical quality too, so that I believe that it will remain of interest for considerable time to come. It is nice to see an article that is prospective, spilling the beans before the harvest. I believe that the field would benefit from more adventures like these, since they help to shape our field. In this sense, I congratulate the authors for doing a great job of the review (some historical events there), and of planning the future life of this breakthrough device, laying open the design choices, and the reasons for them, and for not just presenting us with a final package. This is both didactive, as will it encourage others to pick up on the open possiblities. Well don. Finally, the paper is also excellently written. Hence I suggest to publish as is.  

In this article, the authors review the 25-year long NMR-MOUSE story. The concepts that have lead to the NMR-MOUSE are clearly presented and put in perspective. The number of problems posed by the portability and non-invasiveness requirements (detection volume, peak assignement, B0 field profile design, …), including those encountered in « outdoor » applications, as well as the solutions that were devised to address them over the years, are clearly presented. The range of applications, from industry to cultural heritage, attests for the considerable interest of the approach.

The manuscript is well presented, with a dedicated prospective section on future improvements showing that the NMR-MOUSE, as a concept and as a tool, is ripe and ready to the next stage, i.e., the development of a routine instrumentation available to non-NMR specialists, which will be the ultimate proof of success. This is a fine review which I believe deserves publication in MR.