RBean, I have had two of this kits. The 1st one with a Zenoah 23. The 2nd one with a DLE 30. Definitively, with the DLE 30 the model flies with more authority. The weight was not an issue, it balanced well with the batteries in the rear of the wing well. My DLE 30 is a side exhaust. With a rear exhaust it would look even better, not having to open the side of the cowling.
My ME 109 is posted in this post.