I have a 5+ acre lake, and I only use oars when I absolutely have to, or if I'm in stealth mode.
When the wind is blowing hard, good luck using the oars, and getting anywhere. I remember one time when it was just me and the dog on my boat, and the battery died. A storm was blowing in, and I had to paddle directly into the wind. The dog was barking and being of no help, so I just hurled him into the water to lighten the load, and kept rowing. Just made it back to shore before the lightning started.
Minnkota is household, but 45lbs thrust is more than you need.
EDIT: I need to refine my last comment. If you're tight on cash, you can get by good with a smaller trolling motor. But the bigger ones are only $50 to $100 more, so if you can swing it, get the bigger one for sure.
