I've only had an issue with HK shipping slow once, then it was stuck after being packed in the warehouse, contacted CS and it was shipped the next day. As long as the parts are in stock they're pretty fast, regular post tends to take longer to pack and ship by about a day though, DHL and FedEx are shipped next day in my experience, and are cheaper than slower EMS.
Anyway, a bigger issue I'd say is that you're diving right into 250 quads. Which are small quicksand twitchy, kind of like starting driving cars with a koenigsegg. On the other hand 250s can generally take a beating, and if racing is what you want odor, why not.
If you're using it as a stepping stone to bigger quads though, you're better of going 450-500 right away.