I got my copy of the Emperor Protects this weekend. (I'm UK based.)
I think it's excellent. DW is not my favourite of the three lines, as I prefer the open-ended sandbox majesty of Rogue Trader, but tEP is a model of how to produce a tight, linked campaign. I've only read the first of the three adventures as of yet, but I love what I've seen so far.
FFG have tackled the alleged "problems" of a Marine-based RPG system head on by giving the players plenty of alternatives to combat - if they want to take them. The consequences of each option are clearly laid out, and there are well developed themes for each chapter that reflect the issues at stake.
I was slightly disappointed that there only appears to be a proper Gazetteer for the first of the worlds within the campaign, (I love the Gazetteers) but it's clear that real thought has been given to linking each of the three adventures into a wider, coherent whole.
It's necessarily more focused, and perhaps slightly less ambitious than Lure of the Expanse (which up to now I think has been the best published 40k RPG adventure) but the way it's written suggests to me that it would be easier to run for most GMs. It's a stripped down contrast to Lure of the Expanse, but no worse for it. I'd say LotE and tEP are now the high water mark for 40k RPG adventures.