Re: Im torn between the 6a 64 or 128 gig
Welcome to iMore!
How much of the storage are you using on the 5s? I've always bought the base models, then with the 5 I went mid-grade to 32GB, so when the 6 came out at 64GB I jumped at it. I'm glad I have the space because it's been half full at times. Since turning on iCloud photo library it's less but I do take a lot of pictures and like to keep a lot of music, so storage is a must.
If you take a lot of photos or keep a lot of music, get at least the 64GB (like you're already considering). If you've been able to live with the 32GB, then you'll double your capacity to 64GB and probably be ok
If you can afford it, and think you may end up using it, you could get the 128GB.