peavey ampkit vs irig vs apogee jam or Griffin Guitar Connect?

What guitar interface should i get to use with my Ipad? IRig is available in Malaysia for RM195! Honestly, it's overpriced. Griffin GuitarConnect Cable is a better deal for being cheaper. It's RM112, available in the Apple Online Store. Still, i don't think these 2 products can match the sound quality of Apoogee Jam since we're talking about digital signal. (Via the dock connector.)