I take your point, and also that of Les, but at the end of the day, they are all Class 66's.
My love of railways is almost entirely an aesthetic one. I do realise that the railway is there to do a job, and I can appreciate that the 66 is a good piece of engineering...but speaking as an ex-trainspotter, I just find them so boring!
I suppose I'm now feeling like the older steam lads did in 1968.