I got my 105 4i left only power meter in the mail yesterday. Hope it will fit and get it installed for an outside ride by the week-end.
I decided at my level this will work fine at $300. I am using Trainerroad and plan to get a Garmin or Wahoo that I can push some of the workouts outside, so I effectively will have spent about the same, but have the workable package. If I feel like improve pass this level and need dual sided, I will put it on ebay.