Playing RAW in two campaigns....good guys starting with Everflame/Hollows mix, have nealry hit 4th
and bad guys in a hombrew campaign world, and have hit 3rd
10 observations
1. Have played maybe 10 sessions in total
2. Enjoying all the little bits n pieces boost, like traits and powers from domains et al
3. no one ahs played a bard yet, but 1st level spells at 1st level
4. The BBEG in the good guy capaign has been utterly annihilated by a huge buffed up paladin (eagles splendor, bulls strength et al). Hard az nailz.
5. Its early but again odds levels seem better than evens.
6. the wizard, cleric and sorceror havent once had to reach for the crossbow. huzzah.
7. Bad guys powers, especially for the cleric, are so much more fun than good guy ones.
8. Good guy races seem to have lots bits n pieces, but the drow, hobgoblin, kobold in the evil party just 'rock the dungeon'
9. I guess its new, its all pretty sweet
10. the 'extra doodad' feats for the barb, pally, etc are great.
EDIT: just re-read original question. Yep sweet spot starts at 1st, i have a suspicion, and thats all it is that where 3.5 got icky around 11th, it may start a bit earlier in PF. we are starting PFS in 2010 and that maxes at 12th so i wont have to relive high level horrors of 3.5/LG