Ecto is a great choice. This guy has a nice YouTube channel, lots of crawlers, and a fantastic crawler curse. Here’s his play list for the Ecto. https://m.youtube.com/playlist?list=PL_WRN9SX4RQjsJhOn6Wz_gDSfGv-WqbPr
He also has some other videos where he puts it against some of his other rigs.
Everyone has great advise here and all the rigs mentioned are good performers. If you want the crawler to look scale while running it a heavier rig with a heavy body like the trx4 defender or the scx10iii are fine rigs. I have the redcat gen8 which fit the bill for scale trail crawling.
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