I mentioned the Stihl MS261 before I knew your intended usage. The MS261 is a Pro Grade saw and IMO is a superb saw. I would not recommend the Stihl MS170, it's a home-owner/occasional use saw and cannot handle continued or hard use very well. I would recommend you go to your local Stihl dealer and discuss your needs. They will be able to point you in the right direction. As ltppowell mentioned above, the MS250 would be a good, medium+ duty choice, but I stand by my MS261 recommendation.

Many have mentioned that non-ethanol gas should be used, along with Stabil or Star Tron. While this is certainly good advice, you would be better served by draining the tank and running the saw dry before you put it up for storage. Additionally, Stihl MotoMix (their pre mixed fuel), while expensive, is an excellent choice for occasional use, since non-ethanol fuel is increasingly difficult to find.

Also, be sure to purchase the necessary safety equipment: a good pair of leather gloves, hearing protection, goggles, chainsaw chaps, etc. And always remember to treat your saw with the utmost respect. Stay focused and keep your chain sharp.

Last edited by High_Noon; 10/21/17.
l told my pap and mam I was going to be a mountain man; acted like they was gut-shot. Make your life go here. Here's where the peoples is. Mother Gue, I says, the Rocky Mountains is the marrow of the world, and by God, I was right.
- Del Gue