DBP for sure. The bugs are beeing worked on as well as an improved 3D engine that will give DBP even more speed. DB1 is very limited in speed as well as many other things. The current version of DBP(1.3.1) have less bugs then the demo(1.2.0).
If you buy DB1 now and you want to upgrade later you won't get the discount anymore cause it's only for a limited time. + your work may not be easily ported. Many have found that it's easier to start over from scratch. If you start with DBP now you code will still work when the bugs are fixed.
[b]Digital Awakening
Game in developement: 3D RPG - The Magic Land
Visit
DigAw.com for more info and shots