Yes, the Harrier is that kit exactly and is far more detailed than the Airfix one. The vehicle kits are from a long-time-closed firm JB Models that closed in 1992, but a model store still had new old stock!
The Intergas boiler is doing fine and our gas consumption is way down compared to previous years with temperatures like those we are currently seeing. The stat that he fitted was a Honeywell Opentherm unit that talks to the boiler via radio and modulates it rather than hard on and off. I have a tiny temperature recorder in the lounge and have charted the weeks since installation of the boiler. This was my own idea and I have emailed the charts to the chap who fitted the boiler. He is happy with the result.
Keep on fettlin'
Colin A