It is the same tweeter in both models. The difference between the two models is bass extension (the HT2-TL's play deeper), power handling (the HT2-TL's can handle higher output) and midrange detail (the W18 in the HT2-TL's is more detailed due to the stiffer, lower-mass magnesium cone).
The HT2-TL's are a higher performance speaker over all. I think most who have experience with both models will say there is a significant difference. But it has nothing to do with the RAAL tweeter per se. The RAAL sounds the same in either model.
- Jim