The best known orange is Cadmium Orange (PO20) which is very opaque and has the disadvantage of being a cadmium pigment, all cadmiums being toxic. It isn't the most popular of colours and isn't an automatic palette choice. Nevertheless Handprint rate it as a 'Top Forty' pigment.
According to Handprint PO71 is a lightfast, opaque and staining pigment of a red orange shade. Note the opaque. I'm aware cadmums are toxic but thought, wrongly it seems, that the newer oranges on offer were also supposed to be more transparent. Actually this question of opaqueness is not always what it seems because nearly all watercolour pigments will show varying degrees of transparency when diluted.
I haven't tried Translucent Orange yet so I'll leave the last word to Jean Haines : "At an art fair I came across a colour I would now be lost without -if you haven't tried Schminke Translucent Orange you are really missing out on something very wonderful! When diluted, it is really transparent, glowingly vibrant and works well with many other shades as a contrast". Wow praise indeed and with her soaring popularity I'd be amazed if Schminke have not seen a sudden huge increase in sales.