Mrgooch,
I run mostly Life-Like engines and dont have a problem,I also have a Atlas U25b that has an excellent draw bar pull.
Ten cars is not alot as I only run 10 to 15 myself.My favorite loco is the Life-Like GP18 sold with the American Workhorse set but can be bought seperatly.For a train set loco this one is excellent in my book.
The newer locos have come a long ways in the last five years. but remember that the loco you purchase will be the most costly thing on you lay-out.
Now about your road name........Rock Island is a nice line
Good luck,
Shane