1.5" is from silver satin and the 1" is wire wrap wire. the 1" is solid core wire and the 1.5 is stranded.

the 1.5 is 1.5 grams and the wire wrap is .8 grams I think I will try a coffee stirring straw and wire wrap wire to see if I can get it lighter.

But if what every one is saying is true they both should work well, the Stock GWS Pico is 36 and 3/4 inch my Futaba is 39inchs and if I calc for 72.130 (ch17) i get 39.9inch