Since you plan to be playing on an acoustic piano in the future, I warn that you NOT get a non-weighted 76-key keyboard as a starter piano.

It's with experience that I recommend getting yourself a piano that at least includes the "graded hammer action." With training on a non-weighted keyboard, the transition to a real piano will be very awkward and unfamiliar, and you'll end up with the need to relearn key touch, which will be a slow and painful process.

Here is a review I wrote on a digital piano at Epinions explaining my experience adjusting to a real piano from a soft touch digital.

http://www.epinions.com/content_248848354948

It's also important to be sure the piano includes adequate pedal features. The pedals themselves should feel authentic. Pedals are of course accessories and can be replaced at any time. But on the digital piano itself, there should be at least two pedal ports, one for the sustain (right) pedal and one for the una corda (left) pedal. The sostenuto (middle) pedal is optional because, in my opinion, the effects can be achieved with agile fingerwork.

http://ask.yahoo.com/20040318.html

Half-pedaling is an important feature that produces a slightly lessened effect of the sustain pedal, which is done by pressing the pedal down partially. It looks like the P70 supports this.

http://www.musiciansbuy.com//Yamaha_P70_Digital_Piano_with_Free_P70KIT.html?source=google

The una corda pedal weakens the sound and dulls the tone of the music by eliminating a few "strings." It is also a direction of play found in some compositions, and you will NOT be able to produce the effect with any amount of fingerwork; it is only achievable through the pedal mechanism. I do strongly recommend getting a digital piano that supports this feature, but it can tolerable doing without it if your budget is limiting.

Please also carefully study the customer reviews and be sure their comments are in line with your goals for the piano. I've read a little about the P-70 and for the most part, people seem to be pleased with its authenticity.

Here's one page of customer reviews I found. Try to find some more.

http://www.zzounds.com/productreview–YAMP70

Hope that helps, and good luck.

Interesting resource for pianists.
http://www.cothse.com/articles/piano-lessons-master-teachers/
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