Agreed, there is a power issue here. I'm not a big arm by any stretch of the imagination (350' or so), and have both a Sword and Tern in my pile of discs that I bought and am waiting to "grow into". I have however tossed both discs on the course and in field work, and don't feel like they're anything alike. For my power the Sword feels like the infamous "longer Teebird" It's straight, and dumps left at the very end of it's flight. It has decent glide and will handle a moderate headwind. The Tern gives me a little turn right before coming back, glides for days, and hates a headwind. I'm releasing both discs fairly flat BTW. As I said, I am aware I don't have the power or consistency to throw either of these discs yet, but I don't see them overlapping at all once I hone my technique.How far are you throwing them? If you are unable to get the Tern up to speed then it will not flip and the discs will likely behave the same.
I FH my Swords to 425' on a daily basis with very little turn, while I have seen Terns, flip up from a hyzer release, turn, and never come out at 325'.