Oh dear - people really have no clue most of the time. It doesn't matter which country you host in the courts will still regard it as being published from the UK if you live and upload from there. Go check out the prosecutions against beast sites etc etc to see cases in point.
As usual Sarah summed it up best. It's VERY blurry at the moment and is much better that way. Be sensible and don't show hardcore outside of a members area if you can help it and there's little if no risk. Push extreme stuff and spend your days looking over your shoulder. Push more mainstream stuff and take a small risk.
To my almost certain knowledge there has yet to be anyone prosecuted for stuff that isn't extreme. All UK prosecutions have been for stuff like beast, scat etc etc
Thankfully the relaxation of BBFC regs to allow real hardcore on an R18 seems to have made the authorities more tolerant across the board
However, nothing is set in stone and if they decided to have a clampdown...
Again, Sarah summed it up best.