Bettas are still fish and still produce ammonia waste, which is still toxic to them. So, if you plan not to do constant water changes, cycled filtration is necessary.
Well yes, but my point being (because I do plan on filtration) do I need pre-cycle it or are they hardy enough to where I can just do large water changes while it cycles?
If you're willing to do 30%+ w/c on a daily basis that's fine. It'll take over a month until it becomes fully cycled, but you can speed this up a bit by adding a small piece of filter pad from an established tank and adding this piece to the new filter.
I've used this method in the past to cycle brand new set ups.
Well yes, but my point being (because I do plan on filtration) do I need pre-cycle it or are they hardy enough to where I can just do large water changes while it cycles?