I'm so torn between buying a spotting scope or high power binos.

I have an ok pair of cabelas brand 8x binos that I'm pretty happy with. And was planning on upgrading them to vortex viper hd 10x binos. But in all reality my 8x cabelas work wonderful for quick glassing and spotting game.

I want something that I can spend time behind and really pick apart the hillsides now.

I'm looking at Vortex viper hd binos or spotter. 15x50 binos or 15-45x65 spotter.
I've looked through both in the store. And in the store looking at deer on the wall. Through the binos the deer appear very detailed and quite large. The spotting scope needs to be on 30x in order for the deer to be equal size. Detail is similar at any power in the spotting scope...just the size of the object looks way smaller. Given its only 100 yards or so across the store at very best.
In the field I have a pretty good line up of areas I hunt. And most distances I typically sit and glass are 300-1500 yards. With 80% of that falling in the 500-700 yard range. I typically stay away from glassing farther than 700 yards so I don't tempt myself into shots I'm not comfortable with.

I'm interested in the viper hd 15x50 binos due to them being light weight and I can still easily free hand them and carry them around my neck. But ultimately I will be using a tripod.

I'm curious at longer distance 1000-2000 yards will deer still appear small through the spotter as they do at 100ish yards.

What would the best route be give my brief hunting description.