I pulled out my Aeroclub 1/48 Hawker Demon today, (such a beautiful biplane fighter I just had to buy this kit), The kit is really thoughtfully engineered so that there is no guesswork as to where all the inside bits fit and the box includes to photo etch frames, for mostly interior detail but also struts and stuff. Now I don't do interiors they bore the crap out of me and I don't see the point of doing stuff that is invisible once built. (I always build my models with closed canopies - I just like them that way, a throwback to my childhood days where I loved to "fly them around).
Anyway the kit has all this etch stuff, plus open cockpits where about 20 percent of this detail is going to be seen, hmm it's in the box may as well use it.. I have to say what a pain in the bum this stuff is to work with, eye squinting fiddly bloody stuff .. This experience has ensured a double resolve I will never buy this stuff to "improve" a model.... BUT I would be remiss not to say, it looks pretty damn good!