M-Powered 8 Essential -> M-Powered 8 Upgrade

[Snowblind]

Don't worry, I'm not asking if there is an upgrade for Essential to turn it into M-Powered 8!! (Do you get an iLOK key with the full version? I presume that's why no upgrade exists...though they could have made an upgrade program that will turn a USB Drive into an iLOK key surely? Would leave it wide open for piracy though assuming the iLOK provided is locked down pretty tight...hmmmm...enough of that tangent though!!)

My question is; where is the best (cheapest) place to buy Pro Tools M-Powered 8 in the UK. I currently have Essential since it was bundled with my fast track, but the lack of functionality compared with the full version is annoying me somewhat, and having read that you can't add additional third party plugins and instrument packs to essentials, I'm going to need the full version sooner or later anyway (assuming you can do that with the full version...anyone care to shed some light on that?)

Thanks for the help!!