I think they're great if used in certain situations, where signals aren't so strong and sensitivity isn't a prime consideration. Like when used as a scanner for v/uhf work.
When people are paying $100 or more for a dongle with a converter I feel they'd be much better served on hf with an afedri or smilar, or as I said an used sdriq - I saw one for $250 the other day, an sdriq puts a dongle to shame on hf.