To initially the most important question, the answer to the compatibility: The elite darts are problems with all the clip system to use blasters. From the Recon and Raider, about Rayven and Long Strike to Longshot and Stampede.
With the new darts are achieved both higher ranges, as well as better accuracy. Where the old darts came into a tailspin, the new fly straight ahead.
The new darts are even a little easier. The foam acts, however, more stable and seems to have a higher density. The darts seem to fly faster. It is much harder to avoid them because they are seen not as good in the air.
For each Nerf fan a must. Try it!