Pros: cheap, astonishing sound for price, reasonable isolation
Cons: isolation middling, odd tip size, reasonably microphonic
These are astonishingly good value for the price. Build quality is much better than you have a right to expect, and the sound is equally so - though mids are promoted at the expense of highs and bass. Great phone as a gift to someone getting into iems, a back up pair of phones, or for phones in high stress situations (gym etc) that you can't expect to last.
Be aware that the tip size is a bit funny - smaller than UE's, larger than Shures. Isolation is reasonable, not fantastic.
Update: I have now used my Shure olives w/ PL50, rather than the supplied foams, and microphonics have markedly decreased.