On an actual scale TFX is the lightest but many are having an issue with the lid being too tight. The spire is great but there people say there is a problem loading the last few balls. Rotors are awesome but jam a bit more than the others. I have a TFX with a speed feed...problem solved. I also have a rotor when it jams I just shake it a little and use the lever to unjam it...it doesn't happen very ofter. I haven't used a spire but I'm sure it you go with any of the 3 you'll be very happy with the weight compared to your current.