I went stock components as Surly offers pretty good stuff stock. I will have to get a new saddle (I'm sure) and a few other finicky tweaks but other than that I think I'll be pretty happy. Surly fever is apparently catching. I still recommend the 520. I'm never getting rid of that bike. It is mine forever. Loves. If I love my Surly half-as-much it will be with me for a loooong time.

I have no idea on the Cross-Check frame weight. It's steel so it'll never be as light as carbon obviously. But I would imagine, if your budget is limitless - you're golden.