I once had a case of Goodstyle for my old 4s and I was already satisfied. The build quality is top, the leather looks very nice and it smells very pleasant. The iPhone 6 Plus fits exactly into the shell and is firmly clamped. Namely to open The cover is only loosely based on (no attachment mechanism such as magnetic or clamp / Velcro) but that does not bother. Increased placement options offer the case this time but who does not need the it will not interfere. A long-term statement I can not give, of course, but the 4S I had a similar case approximately 1 year in duration use.
