ORIGINAL: Skullbasher
I have to second the stock head. For the exact same reason.
An aftermarket head can accually kill your engine. If the head cools too much, the piston sleeve will not expand to proper size and will cause premature wear on the engine. I would rather run my engine at 270f than 180f (assuming it is still lubricated).
I got a hardcore racing head a long time ago, and now I have a peice of $40 aluminum that I only use for pictures.
The is why I reccomend the GH head, it is very slightly better, meaning that it doesn't overcool. 7 gallons through my still strong trx 2.5 is proof enough to me. I found it seemed to lower my temps about 20 degrees on average. However, I am talking about in warmer weather. I did pick up a new stock head to use during the winter, and I actually wrap it in foil and a sock. But for running in normal 50-100 degree weather the GH head is awesome.