As far as I can tell, signing up immediately gets the ad-free aspect. HD is still to come. Their non-US shipping charge is high but they cover VAT and import fees, so the overall price ($48 per two-months) gets it shipped to your door with no nasty little surprises.
As mentioned, they currently have no plans to have a video-only subscription without the box. So anyone who doesn’t want the physical items or who is outside of their supported countries is also out of luck for now.
Having said that, they tend to be good with feedback and there’s a lot of active chatter on various anime forums so I wouldn’t class this as set-in-stone quite yet. it is certainly the case for now, though.
As for my personal thoughts, I’ve already put them up here: