just to update everyone, i painted the car in question and mixed the halfords paint 2:1 with hardener and 20% thinners same as i do with the paintshop stuff, got a decent finish so seems to work!! (it was a solid coat not basecoat. i sprayed a different car with my usual paintshop paint today and it painted so much better though. verdict is... ok if need be but use paintshop stuff if you can get it. the only thing that confused me a little is if it is as everyone says, cellulose based, i mixed with hardener and thinners that were 2k and it worked fine, no reactions so im not sure it is cellulose or it would have reacted.