300 hours is not very long! I dont think you really understand the rating system.
Top handled saws are not dangerous! Any chainsaw is dangerous, but a top handled is no more than any other saw.
The Stihl 170 is a joke, dont even bother.
Go to some different shops and see what you like, hold them and see what is comfortable. Ask them about other machines, good and bad. Then decide what fits YOUR needs best, I can only tell you what I use and fits my needs.