I have the SE270D which is the combo machine. I love it. I also have the PE700II which is embroidery only but has the 5x7 hoop size. I couldn't be happier with both of mine and I purchased refurbished ones from a dealer in AL. Super service although I live in MS!! I paid less than $400 for my SE270D and I think the 400 is just an update.
Edit: Not sure how the Walmart machines are covered under warranty. Just be sure to check to see where you would take it in for repair since they have a 25yr warranty. Just saying...