Ex mk5 owner, a current mk6 GTI owner and mk1 Leon 130 tdi current owner.
The Leon is from an engineered point of view superior screwed together and better thought about from a design engineered point of view. Its better undersealed, does not suffer all the rust issues the mk5 does. All parts are cheap and better engineered. its black inside but does not rattle like the mk5 or 6 as its better designed and engineered mountings afterall its an old Audi a3 dash. Does not suffer the ageing stickyness of touchy feely plastics or modern plastic easy marked syndrome.
Yes its not independent rear but the simple engineering is a bonus for long turn ownership. The engine don't seem to suffer many design issues.
Intact I'm still not 100% which to keep! When the time comes to make the choice.
Head as a design engineer says keep the Leon without a shadow of a doubt there is no contest......but the hart says the GTI as I'm a GTI fanatic....