The G38's I have are magneto ignitions and have plenty of power and start right up by hand once you get the procedure down.
Yes they weigh a little more than some of the newer engines and aren't good choices for serious 3D planes but they last a long time. They are great choices for any warbird,or scale plane. I have them in a Morrisey Bravo and a 4-Star 120. You didn't say what you like to fly but as far as an ARF the Great Planes Super Sportster is similar to the Sig 4-Star 120.