The Opel Speedster is another name for the Vauxhall VX220.
The VX220 is fundamentally a luxury Lotus Elise, given that it has such niceties as a radio! It also has a larger engine - a 2.2L GM lump as opposed to the de facto (for British track cars) 1.8L Rover K-series.
I've actually driven a VX220 in anger, and I have to say that it's a cracking car. Nice to look at in the metal, it's got smooth power delivery all the way up to the redline, and an unusually nice gearshift for a Vauxhall.
Not a bad car at all.