I'm new to this forum, but thought I'd give you my tuppence worth on Glenlough. In my opinion it's a cracking site, great location, good bands and good craic. I've stayed there about six times, though changed to a different campsite 3 years ago. Reason for the change was that the showers at Glenlough weren't the greatest. They were clean enough but really low water pressure. I always coped, but my missus came with me for the first time 3 years back and I didn't want to spend race week listening to complaints about showers. Ended up at Braddan Bridge T.T campsite, really good facilities, though bikers were a rarity and no bands, so have always missed Glenlough. 

Due to a dodgy back, I've decided to give homestay a try this year. Some of my mates are back at Glenlough though, so might come down for a visit to get the craic.

A good tip for watching the racing at the site. There's a really good spot on a grass bank about a hundred yards or so before the entrance to Glenlough, coming from Union Mills. When the road's closed, head through the bottom field of the site, across one farmer's field and you're there. Really good spot if you're running late on a raceday, or not fussed about moving for the day. Bikes passing your feet before tipping into the right hander at site entrance.

I'm sure you'll enjoy Glenlough anyway.