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I sided with the railroad and found that even the baddest BoS in power armour could not withstand my stunning supersledge.Yes, there'll be a point where you have to pick who to work with and you'll antagonise at least one other faction who you spurned. I sided with the Brotherhood because of their shiny toys (and because they did seem like an organisation who could help the Wasteland) and that was actually pretty good. I've also seen the Institute play through (ManyATrueNerd on YouTube) but my next play through will be siding with the Railroad.
I'm curious about post-completion differences between the factions. I have the guide, perhaps I should RTFM!