[barrysloate]

I'm trying to think back over the years how frequently each have appeared for sale, and while E107 is tougher, I still think I've seen roughly the same number of each. Part of that may be because E107 is a set of 145 or so, and E103 is a set of only 30. Again, I'll say E107 is tougher, but not by a huge margin. Now of course, if you are talking about completing a set, E107 is way way tougher. But if you simply want to buy a common as a type card, they may be closer than is generally assumed.