DCC and computers

For some time now I've been researching DCC systems, and as I'm currently on a very tight budget, trying to find the cheapest solution possible, that still leaves many features found on the more expensive systems.

I initially settled on a NCE Powercab , but then someone suggested to take a look at the SPROGII.

This little device was designed to be used with JMRI software (which is FREE), to program decoders. However, partly thanks to the power of the JMRI software you can use it as a DCC system throttle, powering a small layout, which is what I have. What's more, I already own an iPod Touch, and there's a nice little app called WiThrottle that through JMRI turns your iPod touch or iPhone into a wireless DCC cab.
I am very intrigued try this out as it would mean minimal investment for me ,just get the SPROGII, (I have all the other soft and hardware already), and a few decoders and I'm up and running in DCC. Should I get a bigger budget available in the future, then I will invest in a decent DCC system, and continue to use the SPROGII to program my decoders on a separate programming track.