I believe the longer Thales 1600629-2 folding blade antenna is what you are referring to. If so, I have tested the performance. I have the flexible arm on it and it sweeps and performs wonderfully on 6m. It easily cracks into the 6m repeaters around here, but they're both around 3600' ASL, so with 5W it is not a problem. Also, you noted the Thales stubby works poorly on 6m and I found that the Yaesu two piece antenna that is supplied with the 817 works much better. I even purchased another one of those Yaesu antennas just to use it on a 2m/6m Woxun HT. Considering its compromise on size, it really performs.
Mancow, I noticed that -3 version just recently but do not own one. My guess is it performs similar to 1 & 2, but my main curiosity was about the 100 ohm reading on the multimeter with the -2 and not observing it on -1. As to bandwidth, they provide what they should as prcguy pointed out. Bandwidth + performance is a reality if one is willing to compromise on one, the other, or both, but you two know that.