I have used both sets. I actually sold my XS' to get the HAT's.
The ID's were run off a JL 300/4 with a Audiocontrol DQL-8 as the processor. My opinion of the XS' were that they were a very good spkr but could be better. They did not have the mid bass i was looking for and at higher volumes i could hear very small amounts of distortion if they were crossed over at their (low end) threshold freq. The overall SQ was about a 7.75 out of 10. Nice and mellow but not harsh and fatiguing. I did have problems tuning my system with them and the tweets. Finding the optimal freq that let male and femal vocals sound equally nice. I would gladly purchase them again if i was doing a 3 way setup where they didnt have to do a lot of mid bass work.
The HAT Legatia's were run shortly off the JL 300/4 and now are run off a ID 300.4. Before break in the sounded like my stock spkrs. After break in they loostened up nicely but the midbass sounded like it was trying to hard to create bass (dont know if anyone will understand that)... I would give them a slightly better overall SQ rating because they play a wider freq range. I give them a solid 8.5. I did not like the L1V2 tweet and listening to the mids with this tweet was not good for me. I exchanged them for SE tweets and the overall sound is much better, they dont color the music as much as the ID's did but that is a plus at the same time as a negative (some music sound too flat and certain nuances the ID's presented were not heard at lower volumes).. Sometimes these spkrs play loud.. a little too loud and they can actual give the feel that your sound stage has been readjusted if you play louder than the volume you tuned your system at.. The L6 Legatia is a kick ass mid and is one of the best to get for a 2 way setup.
Both are very good and above average drivers but the HAT is a little better IMO. If cost is a issue the ID is a great choice. I would be glad to run either set in my car.
....scott B./DAT and Eric S. all voted with very predictable results
I would have chosen ID too even if it isn't quite as good as the HAT. I'll put the Arian against the HAT any day of the week!
'16 single cab Ram Tradesman ST with HEMI...Pioneer avh-501ex...Helix dsp.2...Helix G-Five...Zapco ST-4X SQ...LPG 26na...Audiofrog gb25...Scanspeak Discovery 7"...IDQ12v4d4...Sometimes you just have to turn it up to ELEVEN