I was puzzled a lot between the samsung s6 and the htc m9+ which were both good on spec if you do a comparison on gsmarena. Here’s the reason why I chose S6:
Camera: Clearly the better of the two. Samsung has had a history of good camera’s and it doesn’t disappoint.
Processor: With an antutu rating in the 67k+ range, its the fastet phone there is, and even the mediatek processor from m9+ doesnt come close.
Design: Its a newer fresher design, and so good to hold.
Battery: even though the battery is smaller, it has fast charging, means I can charge to 50% in about 20 minutes.
Touchwiz is much improved. If you’re ruing the old heavily loaded GUIs with a lot of apps, its done a good task of hiding them and making it look classy.
Split Screen. This is just for show value but definitely a good option.