I saw the new lineup during their last U.S. tour supporting Carolus Rex, and IMHO you won't be disappointed. After getting blown away by their previous PPUSA performance, I was skeptical as well going in when they came through, but they made a believer out of me. All of the high energy they are known for was evident. The only disappointment I had (being a keyboard player) was that all the keyboard parts were previously recorded and piped in over the P.A. instead of played by a living human being...they didn't have a permanent keyboard player yet for that tour. I cannot find anything that states they have filled this position as of yet.
Sabaton's Wikipedia page says that "In November 2012, drummer Robban Bäck decided to take a break from touring due to becoming a father. Snowy Shaw will replace him as touring drummer." I don't know if that will be the case when they appear at PPUSA this year, though... wouldn't that be a hoot?