I'm torn by Tim's comments between the desire to make a model as accurate as possible and the reality of producing a buildable and cost-effective product! Pete has used an etch, i.e. a two-dimensional technique, to represent the grille which is in reality a three-dimensional louvred assembly. This, in my opinion, doesn't seem an unreasonable compromise given the size of the part, although being on such a prominent part of the loco it's important to get it right. Also, I would be surprised if even the world's most talented modeller would be able to build a genuine 3-dimensional slanted grille of this size! There can't be more than 0.25mm between slats. The nearest thing I can think of is the cant rail grilles in Shawplan's 'Extreme Etchings' range (for the Deltic, I think) and these are considerably bigger than the Class 90 horn grille.
Whilst I do appreciate that, the thing is (as Jim has said) Pete's products are generally higher-end in terms of price, so one would expect that if one is shelling out a reasonable amount of hard-earned, one does expect to get something that is
right and no question about it.
As for the dimensions of Hornby's model, I can't think of a way that the PH Designs parts could do anything about this. On balance I could understand if he would rather produce a kit to match the (incorrect) model than one which needs additional skillful work to produce an exactly-accurate nose end. Those keen to produce a model which is as accurate as possible can still do so by doing (to quote Tim ) 'a spot of modelling', with or without the PHD parts as an aid.
From what I can see, while the inserts go in the space exactly as moulded, it appears that the covers for the lights and
the horn grille overlap, instead of merely cover that space. It would seem to me that all that requires doing is the height reduced for those parts only, which doesn't need to be much. As Jim says quite rightly, it won't be a difficult one to fix at all.
In my view it's still a massive improvement on the RTR model, especially you consider the number of modellers who are happy for their locos to look right from 'normal viewing distances'.
It is, but it's been rather let down by being a bit on the tall side, which is where the extra two slats have crept in. The top one shouldn't be there anyway. This saves one slat (minimal) and then just a single gap and a slat (0.6mm overall?) needs to go and it's "bang on". A closer inspection of this image here
will show that there is a lip below the grille which is part of the lower angle of the nose. On Pete's test model this has vanished, bizarrely.
By my reckoning, just 0.3mm from top and bottom should sort things out. Also, the surround to the light cover should be wider at the side edges than the top and bottom edges. On Pete's etch, these are very much the opposite and there would also need to be a half-etched line on the outside edges to portray that edge of the surround. Again, these changes are not difficult to sort and I look forward to seeing if Pete can indeed do this.