We did a Safe in our first VC round (and then converted it in a priced round later), and it was an easy, fast way to close. I had to convince our investor to do one because it was their first, and they also had a very positive reaction to it. Deals die because of time and we were able to get the deal done and get back to work. I would definitely do one again and I think the downsides are overblown.
Second one was a priced seed but honestly it was more like a classic Series A. One after that was a larger priced Series A. Second round we put together a board, didn't do that for the Safe round which was intentional on my end (instead we had a great informal meeting cadence)