I can't tell you the bandwidth, efficiency, or the "Q" for any of these antennas. However, based on my own personal experiences years ago with my mobiles...I would guess all these 1/4 waves would likely perform pretty close to the same. That is assuming good installs with all comparisons made on the same mobile setup...within a reasonable time frame considering obvious conditions locally.
Other than for antennas with substantial matching losses, I can't tell you why some antennas seem to operate quieter than others. I seem to recall, "quite receive" is not a quality that is always consistent either. However, with that said and within reason...I don't believe all the claims we often hear repeated...about plastic vs. metal in antennas.
530, I voted for 5'-6' Skipshooter, simply based on your reporting to us that the Skipshooter worked fine and made lots of good contacts. I figure the Predator 10K is an equally good antenna. However, based on its low cost...the Skipshooter is just more practical in every way as I see it.
I think you have both these antennas, what do you think about their differences in noise?