I had a Sprint and sold it...could not forgive myself, and bought an Elan a few months later. Boomerang jets are a pleasure to fly, very stress free flying
One thing to consider: I used a P80se in both models,. My Sprint came out tail heavy (easy to move components to achieve correct CG). But my Elan came out very nose heavy, so much that my cockpit compartment is almost empty[X(]. Be prepared to mount the batteries far back, some puts the batteries over the wheel wells or even under the turbine (I am not to sure about how smart the latter is...).
In the end, I ended up adding 50gr at the end of each boom.
When hinging the flaps, make sure you get lots of deflection AND check that the flaps don`t bind in up position before gluing the hinges. I had to sand a bit on each flap to get a nice flush fit in the up position.
Full flaps on my Elan is close to 90 degrees deflection (so it is actually more like speed brakes than flaps).
The Elan flies similar to the Sprint, maybe slightly faster at full throttle. Slows down really nice on landings