The Mighty Mite is a very popular portable RO/DI unit and works well for its size. Bring as small as it is it does have some drawbacks though namely shorter filter life and higher cost of ownership since the filters need replacing more often, often cost more than standard sizes, are harder to find and come in limited micron ranges.
For short term or if you only make small amounts it will serve you well though. If you don't already have one, get a good handheld TDS meter ($25 or so) to determine when the DI needs changing as exhausted DI resin can be worse than no filter at all since it releases weakly ionized substances back into the treated water, often in larger quantities that it was to begin with. Use the TDS meter on a regular basis.
Great score by the way!