I'd like to add my only experience of dealing with DC Kits. I wanted to add sound to a Bachmann Class 37, so I did a lot of research on various forums about what sound was the best, where to mount speaker(s) etc, and finally decided to go for the Legomanbiffo sound. I found out that I can only buy this through DC Kits, so an order for "my xmas present" was placed via the internet. I live in the north of Scotland, so was pleasantly surprised when it arrived 2 days after placing the order.
Xmas day arrived, and after prepping the veg for the wife I decided to have a go at fitting the chip and supplied round speaker, which I had read on a forum somewhere would fit under the fan unit in the roof. To cut a long story short, it wouldn't fit, so on boxing day I ordered 2 sugarcube speakers from DC Kits - they arrived today, 28th, much to my utter amazement.
I cannot fault DC Kits for their speedy handling of orders at what must be one of the busiest times of the year, their service has been absolutely impeccable.
Oh, and for what it's worth, Legomanbiffo's latest 37/0 project sounds awesome with 2 sugarcubes mounted one each end in the nose.