The 5.5t motor is still too much, the lowest you ever want to go to is a 6.5t and even that will be mighty quick. Your also in good company as a lot of people are coming back to RC from a 20+ year break myself included although its more like 25 years ago for me. The Lipo's you have chosen are spot on, excellent value for money.
My first off roader was a Tamiya Falcon, then changed to a Thundershot, then i found girls!!
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SHRCCC Committee - Membership secretary & Treasurer.
Amature racer, professional crasher.