While the 435 is more powerful, that power is offset by the relative hassle running a gas saw. Noise, fumes, starting all sway in favor of the battery saw. The attached video shows that the actual cutting time is short so unless your cutting all day I'd go with the battery saw. BTW, the battery weighs an ounce shy of 3 lbs, so carrying a spare is unlikely.
The video cutting an 18" log is easily worth more than my chatting, so spend a minute and watch. BTW, that deadfall is above 11,000 feet, getting a gas saw to start at that elevation is iffy at best.
The photo shows the chain case and cover after one tank of oil, about 2 full batteries. The liberal oiler attracts a lot of wood chips. The 2nd photo shows the blocks and limbs from 2020 trimming, see update.
While I intended to use the saw for trail maintenance, that's not how it worked out. One year after purchase a monster forest fire 10-miles from my home changed everything. I embarked on a quest to prune/trim all the trees surrounding my house. That quest continues to this day. To date I've removed low/dead branches from over 100 trees in excess of 10 acres. Many times on my knees and even sitting. This battery saw did 95% of that trimming. My OEM chain has been sharpened to almost nothing left. Purchased two more chains.
The battery and saw have never failed. I've been through over 3 gallons of chain oil over that span. The 4AH charge is such that when it needs a recharge, so do I. I can't imagine using a gas saw for such awkward work.