Hardware spec differences among the four carrier variants S8?

[Niubee43v3r]

Hey guys, is there any hardware spec differences between S8 variants, say Verizon and Sprint, ATT?

I've seen people saying that Verizon S8 is unlocked naturally but do you need to activate it with a verizon sim first right? I heard for iphone 7 it's like that. Does Prepaid SIM counts (ie. Tracfone sim using Verizon network)?

I'm trying prepaid vendors so want to have a model that has the best flexibility potential. I understand there would be a carrier unlocked version, but based on my S7 unlocked version experience, no support from the company...

Thanks in advance.