Both can be cheap, but the Philippines has (for me) far superior beaches, perhaps the best in the world, and diving there can be just as spectacular as it is in Indonesia. Both can be cheap, but both can also be wildly expensive. I think your money tends to go much further in Bali in the cheap places if that's a consideration. There's plenty to do in both places, so I don't think you'd go wrong with either one, but to find everything you want, you'll have to do more traveling around in the Philippines than in Bali. In the former, you really need to do some island hopping; in the latter you can stay in a couple of places on Bali itself (or visit Lombok for a third) to get the different flavor and experiences.

thanks for the input. do you think ten days is enough to visit lombok, dive, and go to bali?

I would want more than 10 days for what you propose in Bali and Lombok, but you could do it in that amount of time if you plan to do your diving there rather than going to Komodo or elsewhere. There are many stellar diving location sin Indonesia. Take a look at this current report: www.fodors.com/community/asia/pulau-weh-and-banda-aceh.cfm

For cultural activities, I think it is very hard to beat Bali.