I've heard people on here say that Velocity's rims were better quality before they moved their manufacturing to the US. Having only had a set of the older Aussie made ones - which were really, really nice - I can't confirm that, but it wouldn't surprise me.
As for 25.4 vs. 26.0, it's just different standards - 25.4 is ISO, 26.0 is Italian. If you really want to go down the rabbit hole of seemingly pointless differences in standards, look up how many sizes of seat posts are out there, lol.
And I'm sure the Sinz cranks are fine, I'm just predisposed to being skeptical of anything with that logos that garish. You can always upgrade them later if need be.