I've sampled a handful of these platforms over the past year, nothing standout amazing or disastrously bad. Quality tends to hover around solid B-level work if you give clear instructions and pick mid-tier writers. Deadlines are usually met, revisions are free in most cases, but support response...
these services can be a lifeline if you're truly out of options, but they're not magic. My friend in engineering used one for data analysis chapters and said the quality was high, but he still had to heavily edit to match his voice. If the writing doesn't sound like you, committees notice. Pros...