Sennhesiser HD 202 are good headphones in your budget, but few things to watch out for. it has a Y-cable, which is not such a good idea as they tend to get unintentionally tugged more ofte. One sided cables are better. Replaceable ones are the best. Also, it has an impedance of 32 ohms. don't know about the n78, but the shuffle isn't built to power 32ohm headphones. So, you're basically going to get low volume output, even at max volume levels, and its going to consume ur shuffle battery a lot faster.
Personally, I use the Ultrasone HFI 780 headphones (*www.amazon.com/Ultrasone-HFI-780-S...dphones/dp/tech-data/B00101XVH2/ref=de_a_smtd). they are audiophile grade headphones with very high fidelity and a replaceable cable, but also have a relatively high impedance of 35 ohms, so I don't use them with my ipod. For portable usage, I prefer earphones, and use the Monster Turbine in-ear speakers (*www.amazon.com/Monster-Turbine-Hig...1?ie=UTF8&s=electronics&qid=1254331838&sr=1-1)