I didn't know there was two but I use this one. I think RRP is £30 but Tescos were doing them for £14.98 but not sure if offers still on.
Official Shakeweight website™, shakeweight, Buy the shakeweight from High Street TV - sky channel 648
I'm doing shake weight every day and I also use Soap and Glory's Firminator cream.
To say its only a 6 min workout its harder than it looks and your arms really feel tighter afterwards.