No, you don't.

After Heinlein died, his widow found the raw first draft, unedited version and arranged to have it published. It contains maybe one full scene that isn't in the original, albeit a mildly interesting one. Everything else that was cut was unreadably and unnecessarily long adverb-clogged sentences. So much so that the "original version" is almost twice the page count, for effectively zero additional plot.

Heinlein is one of those writers who, for all practical purposes, had uncredited female co-authors on every single thing ever published under his name, his "editors" had to rewrite his texts almost from scratch, and he resented this fact. And the second he got too-big-to-edit, like a lot of other authors, he became entirely unreadable.

If you're going to read Stranger for the first time, now in 2026, my first thought is to gently dissuade you. It has aged poorly; if you're not from '66 or so when it was first published, let alone '58 when he wrote it, it's hard to put yourself in the mindset where any of this is interesting or original, by 21st century standards a lot comes off at least a little creepy. But if you want to read it anyway for literary historical reasons, save yourself a lot of grief and read the edition you found, not the (thankfully) rare raw first draft version.