Thank you all for the encouraging comments...
Joel
I've got it at the end of November, and started the work in early December. I was finished in a little more than a month. I did it in a speed-building fashion, though, so I'd say 2-3 months are more than enough -if you can devote hours every week. I was pressed for time (review), and my fiancee was busy with her course and job, so I had no real social obligations...
st Miller, James

It does feel like climbing a huge mountain, but if you're reasonably seasoned veteran (have been in the hobby for a while), you should be OK. The tiny plastic parts that break can be replaced with wire (as I would have done so had it was not a review sample), and the real difficult issue, the tracks are not that difficult, either. And -I'm going to say sacrilege here- so what if you can't/won't attach some tiny part to the engine? (I've left out the decals for the dials; because of the cab, you can't see them at all. You can simplify the build considerably by only building the parts that are visible -for example you can just put the floor plates down, and then glue the levers in place... I did the whole shebang because of the review, but if you wanted to, you can cut some corners.) And to be honest, it did give me a lot of sense of accomplishment. Normally you build a kit, and it just the same: glue turret, hull, damnthoseannoyingtracks, weathering, done, get me the next one. This I felt I actually finished something difficult... so I think it's worth jumping into building one

(Be prepared though: the model will not look like a dozer until the very last minute; you keep working on it, and the progress is not visible. It can be a bit demoralizing. But once you start putting it together at the end...) I'd be curious how the competitor's model compares. I really liked Miniart's "purist" approach: everything in plastic.
The cab, unfortunately, does obstruct a lot of the detail, though...
Mike
Thank you for the link
As a last note: the suspension's top cover CAN be left off to show off the suspension; I found a photo online where a D7 has been serviced with the cover off...