Hello Kevin,
It seems you have done some homework, as both those hotels are in basically good locations, not far from Carmelitas, the wealthiest part of Asuncion, where much of the shopping, restaurants, bars, etc are located.
I have only stayed in two hotels i n Asuncion...the Excelsior, which was nice, though pricey and downtown (where you defiantely DONT want to be, especially at night). The other was Hotel Los Alpes, located more or less in the region of your two hotels. Los Alpes was nice and a double was about 65 bucks. One bit of advice. if you will be here in summer, a pool will be something you will want.
good luck,
Mike