Planet models are very good at churning out decent quality resin kits of some of the more unusual subjects. As with most of their offerings, this one is solidly cast, although as is usual with the genre, the surface details are a little heavy and simplistic. The internal cockpit details are generous, but again rather simplistic and a little "rough". But as ever, if you want a model of something more unusual, this is the price one pays.
I can't comment with total authority on the accuracy, although it looks right. I have read that it's a little under-scale, but my calculations don't seem to bear this out.
My instant reaction to the kit parts was that the heavy, solid wings appeared to be a bit much for the relatively flimsy two fuselage halves. Being resin, too much strain would potentially be disastrous so my first resolve would to strengthen the fuselage with some struts.
The cockpit tub went together pretty well, fitting the instrument panel was less precise, and took some messing about but I got it to an acceptable state in the end. Planet provide a few nice etched details, including reasonable belts so I installed and painted these. Not too much effort was spent as things won't be that visible.
We now move on to the one major flaw in this kit. The wings are dead flat, and this is wrong. The aircraft should have a 3-4 degree upwards dihedral on the tip sections. Indeed, this is obvious from the cover picture on the box, but Planet seem to have completely ignored this. Unfortunately this was too much for my neurotic brain so I chopped the end of the wings, drilled some pin holes and re-connected them at the correct angle. After a lot of filling and smoothing this seemed to have worked.
The Welkin had, as far as can be ascertained from the limited references available, a fairly complex rear canopy sliding structure and although Planet have provided etched canopy supports, the underlying mechanism is not represented. So, admittedly using a little artistic licence, and based on the best references I could fine, I cobbled it together from spare etched brass.
So there we go, a decent model kit of a little remembered aeroplane. Hard not to recommend it if you want to build a 1/48 Welkin, if only because you don't have any choice.