I know this isn't the kind of answer you're looking for, but the real truth is the techniques described in books or on DVDs are only a tiny percentage of what makes magic effects powerful. So, the answer is, yes, a colour change is an acceptable effect to perform if you perform it in an acceptable way. In fact, performed in the right way, you can get great reactions from a jog shuffle. The moves or techniques are just tools or, to give a more artistic analogy, your palette of colours. So, asking whether a particular technique is an acceptable effect is like asking if green is an acceptable picture. The answer, of course, is no, not automatically, but when contextualised by means of creativity and turned into something more than just a blob of green then yes, green can become an acceptable picture. And, similarly, a colour change, a jog shuffle, a coin retention, a memorised stack or any other technique you could name can become an acceptable effect.