The Galaxy S4: still the Android phone to buy?

Although the Galaxy S4 was released more than 6 months ago, it has since been one of the best and definitely the most popular Android smartphone. However, given the rate at which new technology is released these days and the rate at which technology is outdated, my question is the following: is the Galaxy S4 still worth buying, especially in comparison to the HTC One and the newly arrived Nexus 5?

When comparing the specs, the Nexus 5 definitely wins the processor race because of its beastly Snapdragon 800 processor, but the Galaxy S4 is much stronger in the camera and battery departments. The HTC One, meanwhile, is the clear winner as far as build quality goes.

Since I'm in Belgium, a country with no Google Play Devices access, I could get all three phones at around the same price unlocked. I want the Nexus 5 because of its speed and stock Android, the S4 because of its camera and battery life, and the HTC One because of its build quality. Given that price is no concern, which one would you reccomend and why? Which of these (and any others if you care to include them) is the best Android smartphone at the moment?