that's unfair!!!! they are both amazing albums. ToS is just out there with the amazing technical guitar, fast, and heavy riffing, great melodies, and great acoustic pieces. However, it never felt like Angra to me because they didn't play as much with the Brazilian sounds like they did before, they are still there but not really upfront. It is a great album, but doesn't really stand out from other PM bands.
Rebirth, was the last album that Angra recorded that still has the Angra feel to it, and I absolutely love it. Again, great guitar work, not as technical as ToS, but still amazing nonetheless. This has Rebirth, Heroes of Sand, Nova Era and the ballad at the end, as well as other great gems.
to sum it all up, both albums are great, but if I have to pick one I would pick Rebirth...but if I want to drive fast, I'll say ToS XD
ps. best Angra album for me is Angels Cry