Stayed at Glacier Campground last summer. Bathrooms & laundry were clean but I think my site was elect and water only. Sites were a bit close together, but there was still enough room. I drove by the KOA and it was nice...but too expensive for my budget.
I'd have absolutely no problem staying at Glacier Campground again and the prices were fairly reasonable.
However, if you want to venture off the FHU campsites, I'd strongly recommend Two Medicines Campground on the east side. They have flush toilets and water spigots thruout the park. It was never hot enough to need AC and really only time I needed power was to shower.
We were at TM for 10 days and it ranks up there as probably our best trip ever.