Although I can't comment on the Imagines, other than to say, they are a fairly new/recently developed setup.......I can comment on the Hertz, as I have owned more than a couple sets of HSK's in my time.
Things to consider with the Hertz Kit in question:
The HSK-165 kits that are now most commonly known and refered to as the 'pre-2008' models are infact quite a bit older and were more or less a hand-me-down design stemming from an even older setup that included the HV1600 6.5" midbass drivers and HT250 25mm Tweeters, more affectionately known at the time as the Hertz Mille HSK-1600 2-way Component Kit.
With what seems minor changes, the HV1600's became the HV165's and the HT250 Tweeters became the predecessor to the 'pre-2008' HT25 25mm Tweeter, both of which made up the, then, HSK-165 Component Kit.
While a great set of components, they definately show their age when compared to more recent offerings from other manufacturers.....for instance, perhaps the HAT Imagine Series....and pale in comparison to their replacements, the 2009+ HSK-165 Component Kit.
Common complaints about the 'pre-2008' HSK-165's has been slight lack of midbass with the need for a sometimes higher crossover point on the bottom side, as well as the HT25 Tweeters being a bit on the bright (not quite harsh) side using the factory crossovers and the crossover point of 3,500hz @ 12db/oct.....although seem to work better when crossed over at 4,500-5,000hz, as well as 'taming' them with a bit of EQ. They also don't quite handle the power that other Hertz drivers are known to handle, as I have experienced first hand on a few occasions.
At this point, the older HSK-165's (I don't think anyways) make the grade as a Front Stage choice anymore. Great Rear Fill, or perhaps part of a 3-way active setup (under the right conditions).....but just not as a 2-way primary setup.
This, of course, is all my opinion and other's mileage may vary......
Hope this helps, atleast a little bit.
Allan