Totaly agree with Yves. The most important thing is to define/find your style. Faked HDRI as you show us is for me only an element that help increase the level of realism of a render.... but this is just an exercice. I use similar technique in some of my pictures. The original picture (Montepulciano) you can see in my gallery. Have a close look at reflection on the bottle. What can you see ? Yes a house and a tree. This objects are part of the whole scene even if we dont see them.... they are reflected by the bottle. So i have added something as a 'real world' only for that purpose. I'm not sure that peoples have seen it. But this is not my main goal... Some details like this you can see in my picture : Street. Look at the reflection on the Jaguar ...