First off, the 205 degrees is fine if you can sit in traffic for an hour and it stays there. That being said......
The 2 core you purchased from Champion should be their American Eagle line. Just make sure that's what you have coming. If it is the regular Champion line, you are either going to get a small 2 row, 3 row or a 4 row. None of those are really an ideal upgrade for your situation.
If it is the large 2 row, then I think you'll see your temps come down enough to put this issue behind you. I'd certainly wait until then before you switch everything back to mechanical. However, if this whole issue was reversed (you had everything mechanical and running 205-208) I'd tell you to keep everything the way it is and just put a bigger radiator in there to bring those temps down to give you a little better feeling of comfort.
