Here are some of my thoughts on the Lightsport. I have nearly 200 hours up on my Sonic and was looking for an upgrade for my coastal flying. I needed a glider with a few extra points in glide to cross the gap at Stanwell.
After 5 flights and about 4 hours on the Lightsport 4 in varying conditions from 10-20 knots of wind, here are my thoughts.
I just loved the extra glide and handling of the glider. You pull on the VG pull the bar in and you go forward not down like my Sonic, the glide on it is just fantastic. If I was 10 years younger it would be my perfect glider but as I approach 60 the extra weight was just that too much for me to consider taking into the future. The weight problem is very specific to me as I virtually only fly at Stanwell which necessitates a 60 metre walk though soft sand every time I land and those extra couple of kilos sure make a difference in the soft sand.
As stated in other posts the Lightsport has the same glide as the Lightspeed at normal speeds. I tell you what a step up from the Sonic. It is in a completely separate class of performance and yet I could still throw it around as much as my Sonic.
The launches and landings at least at Stanwell on the Lightsport were a no brainer. I would even say that the Lightsport landed just as easy as my Sonic and had better flare authority due to the narrower chord.
So bottom line if you are under 60 and want a glider with the performance of the Lightspeed, fly on the coast where you want that better handling of a king posted glider close to the cliffs at low speed than a topless and don't need those extra points in glide at high speed, then I would say go for it, it is a great glider.
UPDATE: Well after loosing 10kg and test flying a Lightsport 3 I ended up buying a Lightsport 3 with Carbon options. The glider weighs 28.5kgs just a couple of kgs heavier than my Sonic. I am now a very happy camper. I have about 30 hours on my new Lightsport and could not be happier it is a beautiful glider.