Just checking. Everytime I think that the discs I'm throwing are too understable it just turns out I'm doing something wrong instead.
For me, throwing using a hyzer-flip, the straightest discs I have are a 172g Champion Viking, a 170g DX Teebird and a 175g Proline Teebird-TL. Start to finish I think the TL is the straightest (if you put enough hyzer on it), the Viking is the longest (it has the most fade at the end) and the DX Teebird is the most versatile but YMMV.
You may want to check out a heavier DX Viking if you prefer the fast, wide rimmed drivers and don't want to pay for Champion plastic. I haven't thrown one yet but I'm looking forward to it.