The F7R engine found its way into early Megane Coupes (Phase1) from about 1996 to 1998 and into the Renault Spider - but not the Scenic! The F4R is found in lots of models and is even supplied to Volvo for their S40 2.0 (I drive one!).
The F7R was first seen in the Williams, but the Willy F7R engine was different from the above ones. The Williams head has larger inlet valves (at 30.1mm), a different inlet system (which is polished) and the engine has a properly baffled sump. Basically, the Willy had to use a modified 16V inlet system due to the space constraint - whereas the Megane/Spider engine bays were more spacious.
I dont know of any more differences than that. The Willy engine and the other F7R units were all on a par in terms of power, but have slightly different power delivery characteristics.