For years I'd buy a "throw-away" department store saw every couple years.  I'd spend time dinking with it every time I'd cut a limb.  Finally, 4 years ago, I got fed up with "cheap". Buying cheap had cost me a fortune over the years.  I broke down and spent the big bucks on a Stihl MS260.  Best decision I've ever made as far as chainsaws go.  That model performs best with a 14" or 16" bar, along with the correct chain. (read GOOD chain)  So, my recommendation is to buy a Stihl "PRO" saw that fits your size requirements, and leave the rest of them at WALMART.