I will try SXX v2 + LRP 4.0T (Octa wind) + Silverpack/SMC 60C 1S Lipo
Are you using HW 1S ESC?
I think HW 1S is good and the play time could be around 8-9min when using 4.0T motor with 1S Lipo.
However, I have not use it before. May be some Ching here could share the setting for reference. ^^