Nickodavidoff --
I heard the Peak Consult InCognito Grande a couple times almost 10 years in the demo room of Peak Consult's "factory," or rather hand-assembly and developement/test facility in Denmark, where they are still home, and to the best of my recollection I can say with absolute certainty that the Grande's were not thin sounding nor lacking in bass quantity, impact or extension. In fact, if we consider the Diablo's to be the "modern" InCognito Grande I've since found it a shame that Per has chosen to use two 9" units in the El Diablo's instead of one 11" ditto, but that's just me and my love for big diameter bass units :) Anyway, what I remember most clearly of the sound of the Grande's is how they were full-sounding with a majestic scale, and one had a feeling that they could cope anything you'd want to "through" at them - in most every regard.
Some years later I also heard the El Diablo's, at the same facility and listening room, and to me, again to the best of recollection and considering the differences in equipment/cabling, they share many of the overall qualities of the Grande's in terms of scale, ease/composure and general presentation, though adding perhaps in mids and highs sweetness and naturalness as well as ultimate spatial ability. The bottom end of the El Diablo's, were I heard them, bordered a wee bit too much on the warm/full side of the spectrum to my taste, and in the context of their placement far from the walls around them and the large-ish room in which they played it made think how I'd be careful about implementing them with equipment, cabling and room - at least to my taste. Still, the overall presentation was no less than wonderfully natural, coherent, and musically involving, perhaps some of the best I've ever heard, and the warm-sounding bass seemed a good match to the rest of the El Diablo's sonic "temperament."
To sum up: to my recollection the Grande's sported a slightly more massive and "intensely focused" bass reproduction, with depths to die for, whereas the El Diablo's are tilted a little bit more towards warmth in this region, and not with the same sense of "focus" I heard/felt from the Grande's. Still, I've come to learn that Per generally "flavors" the bass reproduction of most his speakers slightly to the warm side in the central and especially lower areas, and this way it's still noticable how the Grande and El Diablo share a commen ground here. And yet, the different speaker models from Peak Consult seem to take on their own specific character in developement, and so what comes out in the end is a deliberately tuned speaker with its own personality, if you will, making The Empress, for example, a speaker that is indeed tilted more to the leaner side in the bass department - probably an indication of the overall balance of the rest of the spectrum.
As is I would definately recommend you to arrange, if possible, an audition of the Grande's. They're extremely capable full-range speakers with a natural sonic presentation that will likely convert most, if not all of your music collection into an informative, versatile yet always musically-founded experience.
