As others have said diesel is optimal for the daily drive, some of them are quick as well. think there is a place for them on the forum as there are plenty of petrol non gti cars. but IMO a true GTi is NA and petrol
tho as far as the pet car/ weekend toy goes i don't think diesel can ever replace a cammed petrol engine. i just don't like the powerband of diesel in such cars, there is just somethign about the induction roar of an NA petrol engine at full chat, the bangs and pops on overun and occasioanly crashing into the limiter that just makes them fun.
Did try putting a PD in a golf 2 as well some time ago tho it was more to be used as a test bed for the wireing loom mods needed to get the engine running but it was taxed and MOT'ed so choiuild be driven around. IMO it was inpressive and crap at the same time hell did it pull but that was the only fun thing it it did it just wasent fun to try and drive it fast down twisty roads it was like all the GTiness had been extracted

so after 2000 miles of testing the engine was extracted