I had a Speed2 19 and would start crapping my pants over 15 knots. I know I got more pies than you too
The S2 19 and the S3 21 don't have the bottom end or upwind pointability of the X-19... by just a tiny bit. The S3 21 has more range and the S3 15 is a lot more fun.
If I were you, I wouldn't bother. Bottom end is what the X-19 is about IMO... S3 15 is about surviving the lulls and boosting like a nutter in the gusts.
X19 its a train ....
When you build apparent wind its unstoppable
I am 200lbs ... and using my Aboards Glider 164 I can ride from 6mph ... Its hard to get going but when you do its all good .... 8mph easy upwind and no problems with transitions .... 18mph and small boards its my limit ... after that almost impossible to hold you edge...
Very light weight, No need to pre fill it ... 5th line safety its a plus
way less depower then Speed3 19m .... and a bit slower ?? .....
My home area is a friendly rival zone of X-19 (3 owners) and Speed3 15DLX (5-6 owners). I must say that 100% of loft accidents in my area has happened to X-19 riders. The kite does not take the gusts as Speed3 does. It's wind range is much lower, lower than 21 wind range.
But of those two X-19 is a more powerful than 15 Speed, so it pulls better in ultra low wind (4m/s). I think it is also a slightly more powerful than Speed3 19DLX but when I had S3 19 the X-19 was non-existent so I have not compared them head-to-head on sky. But it does not beat 21.
X-19 has a lot more bridling compared to Speed3. So it is a bit harder to handle on ground. But X-19 is a fast filler at launch. Relaunches as expected similar to speeds etc. Wing profile of X-19 is efficient because of profile battens. It parks over the zenith which is scary to me but the kite is stable. Full 5 line safety.
X-19 better turning than 19&21m but 15m takes the win. But one X-19 friend hopes that this bar would be wider to make X-19 turn even faster. So he thinks standard bar is too narrow. Depower throw is quite long so sometimes it is hard to reach the depower strap.
Those are my feelings and what I've heard from X-19 owners.. I've flown the X-19 on ground and handled/helped many many times.