The Phu Inn is a 80-odd room budget hotel a two minute walk to the Air Conditioned (main) bus terminal. Nice big but basic rooms were very clean. We had no complaints about comfort of the bed or pillows, towels were a bit on the thin side though. Small fridge, air con, almost 200 channels on satellite (every language you could imagine), but loads of sports and news and the odd South African soap . Incredibly fast and free Wi-Fi, very pleasant staff but not much English spoken. Right next door to a huge hawker market, seems as though it was open 24 hours for breakfast, lunch, dinner and middle of the night snacks, but no noise. Khon Kaen is a fairly large town, big market and plenty of eating opportunities, mostly fantastic cheapies, but a few decent looking and well priced western restaurants.
Interesting enough town to spend a few days en-route to Laos - visa processed in 10 minutes, costs about $5 more than at the border but well worth it. You can get a visa on arrival, but the queues are huge and if you get the international bus (much easier, no touts, no arguments and only BT180 all the way through to Vientiane) you must have a visa already or they won't wait for you - 3 westerners had their bags taken out at the border when the driver could see they'd be in the queue for a good couple of hours.

All in all, very happy, and only TB350 per night.