Just to clarify, my sense of it being cheap arose from the perception that these usually go for £100-125 or even more, although I accept that eBay can be erratic. By comparison Konaman1's 1996 Kilauea frame (Columbus Cyber) recently sold on eBay for just over £200, having failed to sell on here for slightly less.
Although Explosifs are worth more than Kilaueas, it is worth noting that the perception that they are of a higher quality has very little substance. Rather, they were designed for different purposes, the Explosif as a race bike, the Kilauea as an all-day bike, virtually the same weight but a slightly softer ride quality. Both made out of Tange Prestige heat-treated tubing, and the Concept tubes that this Kilauea is made of were ovalised and tapered and thus more expensive than standard Tange Prestige. Back in 1994, the Kilauea frame sold for £349 and the Tange Ultimate Explosif sold for £399, not all that much more.