Assuming the bed is in good shape, I LOVE the HGI beds. I prefer the full firm setting - perhaps dialed back by an 1/4 inch. There are times where the beds don't seem to be completely functional however.
The one aspect where I prefer HI over HGI, is the size of the bathrooms. They are just too cramped in most HGIs. I really hate having to battle the toilet which blocks the counter.
Course, one of the most important differences is the opportunity for REAL food at breakfast. Granted, it does cost extra... but I like being able to have freshly cooked-to-order breakfasts available on the property. All the carbs at HI get's old really fast on longer trips.