I have a couple of 435 saws. I skipped over the 440 saw as they seem identical but the 440 has an 18” bar as opposed to the 435’s 16” bar. I just figured the saw would do better with a 16” bar. I have had both for a while now and use them fairly regular. I haven’t had any problems with either. Both were refurbished saws from Northern Tool. They had them on sale for $159. I bought one about 5-6 years ago and liked it. A year later they had the same sale/deal so I bought a second. Both looked like new saws. I noticed the other day, like a few days ago, Northern Tool had the 440 refurbished saws on sale for $179. I came close to buying one and still might as I have been pleased with the 435s. If Northern Tool still has that deal for the 440 refurb you should just buy it and not worry about the 435. I just looked and NT still has the deal:
https://www.northerntool.com/shop/tools/product_200620291_200620291