Ours was not a conversion but a new build Calfee Di2. I wanted the widest range we could get out of a 2x system. We're at 52t x 34t up front with a 40t x 11t cassette. It was set up with a K-Edge long derailleur arm. We didn't try the Wolf Tooth Road Link. I really don't know which is better.
The bike shifts fine despite the fact that we're beyond the recommended range up front (18 tooth difference).
My biggest complaint is that the drop from the big ring to the small is huge and I need to make sure that I notify my stoker about this upcoming drop. However, we do use the full range when climbing & descending big hills.