Touchwiz always annoyed me the most and never seemed as clean cut and nice looking as sense. Always felt that HTC seem like a better build quality too though never had a major issue from any smartphone so hardly as if any are bad, just Samsungs usually feel more plasticy from my experience.
Rooting is really simple, well it was for me on my S2 so I would imagine it would be very similar for the S3, but if it's pure or the latest Android you want then that is where the N4 and other Google Edition handsets will come in to play as they will have no bloatware and will receive updates to the latest version of Android first with no faffing or geeking about required.
It entirely depends on what the customer sees as priorities for them and how much they are willing to pay for what they want as there isn't one handset that is the best. I was only fussed about being able to browse, e-mail, stream media but then wanted something with an extendable battery and good community support. Top end phones now would be complete overkill for me and would therefore be an unnecessary expense too but it entirely depends on what you want from the phone.
