I'm not sure if I correctly understand the question ADB.
Presumably people will generallly assess a new BIR with the curry they usually eat and like best (I know I do)?
BUT!..if you want a good assessment of their true capabilities (wrt taste, aroma, appearance) you would be better off assessing it with a curry which is as close to their curry base as possible (ie. a mild, non-creamy one such as a straight curry, bhoona or mushroom bhajee).
I say this because I believe the taste and smell is primarily derived from the curry base and other curries (e.g. madras, vindaloo, korma, CTM, etc) can only mask this with their additional spicing (chilli, cream, coconut, sugar, etc).
I know that a true test of my own capabilities is not with making madrases and vindaloos, etc (which I like best) but with the "simpler" (i.e. milder and less spiced) curries). If you can get the "taste" and the "smell" (i.e. rich, deep, savoury, smokey) with a simple curry (like a straight curry, bhoona or a mushroom bhajee) you know that you have truly cracked it!