I was Backer #173 and I chose the 1000 (EM) version in the Silver color straight away. I did not upgrade to it, it was the original order placed.
I do not have a shipping confirmation despite the fact they said the first 100 units shipped Feb. 28th were the 1000 (EM) model in silver, and the next 200 units shipped March 14th were the 1000 (EM) model in all colors.
So I too am disappointed, but for slightly different reasons than you are. I have trouble seeing how they have actually adhered to the original shipping schedule that stated 300 units shipped by Mar. 14th.
I also did not like the fact that after stating only Silver 1000 (EM) model units had shipped prior to Mar. 14th, a guy pictured at SXSW had a red unit in his hands on Mar. 13th at the SXSW Grammy party. Was his unit shipped to his hotel that week, and if so why is it there days early, and in the Red color?
Adding to that, Scot Hull then posted a video on or about the 14th (so posted either late Friday the 14th or early Saturday the 15th if I'm not mistaken) in which he is holding a Green unit. Not only was there supposed to have been nothing but Silver shipped to that point, but the original run of Green enclosures was said to have been rejected by LH's QC in Kickstarter update #40 on March 12th as being too drab olive in color and not the brighter green they wanted. Maybe Scott lives nearby LH Labs and opted to go pick up his unit rather than have it shipped?
So to sum it up, it's unlikely the shipping dates have been met and it isn't just the standard 450 model or even the 720 model that aren't shipping, my Silver 1000 Backer #173 hasn't shipped either and one of the recent Kickstarter updates indicated they likely won't have the 1,700 additional units originally slated for March 28th shipped on time either, but "maybe" an additional 300 would ship by then. That's quite a big difference.
At this point I am pessimistic a Silver 1000 (EM) unit, Backer #173, will ship by March 28th. I hope they prove me wrong.
However if these delays are deemed necessary in order to ensure ultimate quality and performance, I am more than willing to wait however long that takes, provided there aren't other Silver 1000 (EM) units being shipped to Backer #s higher than #173.