I've got one of the super cheap mini chainsaws. 100mm blade. It takes makita batteries, which I already have, so no issue with poor quality batteries. The saw is obviously of low quality but it works brilliantly. Cuts through thick branches with ease and is easy to use one handed. Way faster than using a pruning saw. The only issue is it overheats and shuts down after 20 or so cuts. Comes back to life after a few minutes so its an annoyance but not terminal. I would definitely prefer something of better quality but this was £20, a makita one is nearly £200 so I'll live with it for occasional use.