Finally made it to Roti Joupa today. The doubles (photo) was (were?) very good, as @ds and others have said — beautifully soft fresh flatbread wrapped around soft savoury chickpeas with a vibrant fruitiness added by the hot sauce and tamarind sauce. If I were to be picky, I’d say the chickpeas were over-endowed with skin, but I did like their texture apart from that.
The bread didn’t seem fried, which puzzled me a little. I thought the bread in doubles was meant to be fried?
Also had the macaroni pie (photo) as takeaway, and thanks for the tip re tamarind sauce — they started putting on the lid without putting any in, but thanks to @paprikaboy I knew to ask for it! The sauce definitely makes the dish.