gsi speedline alloys

i have two nitro rc cars for swap/px first is a 1/10th nitro rs4 dodge viper (electric start!) exactly the same as this YouTube - HPI Nitro RS4 RTR3 Evo Viper Speed Test second is a 1/8th hyper7 off road buggy - cost me £370 and has hardly been used.. exactly the same as this...