They'll send you whichever you like.
I purchased the machine offer from LA Tan, and got a litre of each of the %s. I've used the Disco on myself for a night out and on 2 clients who both loved it. I've also used the disco on myself if I've not had time to tan early enough, so I've been sprayed and left it on only about 3 hours, it has still given me a great colour.
I have to say the people I have sprayed have been very happy with the colour, it's very natural looking, and some have said it's the best tan they've had/seen.
I've read on here that other brands wear off better, but I'm afraid I haven't got round to trying any others yet (have some samples in my cupboard, I must find someone willing to spray me!)
Give it a go! Lou x