Awkward user interface - and read the fineprint

Youre only buying one sound out of the box, so if app "costs" $0.99 beware that if you want additional sounds it may cost you as much as $5.98 in total. Perhaps worse, as others have said the UI is awkward, so the implication that you can show up somewhere and sound like a Ferrari to others would be hard to implement.

22/3:(5 about XLR8