Maybe price has a lot to do with it.
I've just specced up a GTI against an R and the R is considerably cheaper over the shorter periods.
I also flung in the GTD just for a full comparison.
Deposit £5000
OTR £26,330 £29,900 £25,765
Term GTI R GTD
x18 £482 £376 £406
x24 £382 £310 £326
x30 £360 £322 £318
x36 £338 £316 £298
x42 £322 £318 £295
x48 £307 £310 £282