Hello June. I found the Astotels in 2018 on this forum and booked the Monterosa, 4 nights. We had three rooms and were quite satisfied. Although there were some technical problems, they were handled efficiently and we got a small discount.
Two weeks ago, my cousin and I stayed for 3 nights in Hotel Joyce, just opposite the Monterosa. This time, no problems, technical or otherwise. We had two single rooms, small (this is Paris, after all!) but convenient layout.
Very friendly personnel, good breakfast buffet and the open bar (free non-alcoholic drinks and some small snacks - think peanuts, crackers, madeleine biscuits) after 14h00 is a nice service. There is a small mini-fridge in the room, with free non-alcoholic drinks.
Between the two hotels, I prefer the Joyce, mainly because of esthetics. On my next visit to Paris (I live in Brussels, Paris is close), I either return to the Joyce or use another of their hotels, in the same neighborhood.
Have a good stay in Paris!