I had a Jetex 50 ages ago & mostly had it on balsa gliders until I learnt its quirks before moving on to
more advanced Jetex powered models. I never got it to work reliably so that was a dead end.

Occasionally one of the local free flight guys will bring one out for a fly, no idea where they get the
fuel pellets, I suspect they are just 40 year old originals.

Like most small models electric flight technology has made tiny jets possible, guys at my club fly
tiny RC jets that cost pennies with amazing performance. - John.