I used AA to add the backside cooler from a Thermaltake IFX-14 to the backplate of my s115x (yes, I'm using the front part too) not sure it does much in the way of cooling mounted like this but looks good. Even with 4" of heatpipe to use as leverage it's not coming off!
You might be right though, depends if the heatsink is bent/uneven or it's just a badly designed mounting system...