a quick trawl of the US golfmkv threw up some interesting info which I will try to summarise.
1. all currently available air filter kits give little or no power increases.
This is hotly disputed by various sides , where some claim big gains.
2. EVOMS filter has quality issues but appears to be most popular + biggest gain
3. Many love the Carbonio , basically an enhanced OE design. But I only found one dyno plot showing +4 bhp
4. The consensus (whether its backed by hearsa or fact !) is that
EVOMS is best for high rpm gains , Carbonio 'may' improve the lower rpm better.
5. APR stopped selling Carb intake as part of an upgrade kit , which could either be cost cutting or that its not reqd. you decide!
so I guess if you like it , buy it but dont expect lots of horses.
Maybe a modified OE box would be better.
As Gaz states at higher levels of tune this may change demands.
However that would mean back to back runs @ Awesome , which commonly doesnt happen .
As I know that if Im going to go there, I plan to get a few things done together so its hard to isolate the hp per component differences.
JohnO