Jim ... when I started I was totally lost too. To say get a 300W motor can be inaccurate, you want the right motor for the plane. Some motors would give you 300W but will only turn a 5x5 prop on 3S but another motor, a bigger one can give you 300W with a 9x6 prop.

Not asking you to go really big but when you say 3.4 lbs you may mean its with a glow set up. When you go EP it might touch 4 lbs. So something like the AXI 2826 is just about nice. Next you need to estimate the right motor to use in the sense of weight to get the CG right. Battery placement and ease of access too. Enjoy the trip!