What do you think of an implant being placed at a 45 degree angle? (Photo)

I was told ( as an option) that in order to avoid a sinus lift in tooth #3 the implant could be placed in an angle ( between #3 and #4( extracted) approximately at 45 degrees as shown in sketch below. Then the abutment would be placed in a vertical position. I'm concerned of the distribution of forces may place an angular momentum or torque on the implant. I was told the bone does not care. Does anybody see a problem with this? Does anyone have experience with this?