The best Hibor rate in the market is Hibor rate +0.5% (certain banks can even offer Hibor rate +0.45%) Cap P-3%. Hibor rate is around 4% now but can fluctuate from time to time.
For example, if Hibor rate at time of calculation is 4%, the mortgage plan with Hibor rate + 0.5% only pays 4.5% interest, while the mortgage plan with P-3% pays 5% interest, P-3.3% pays 4.7% interest. (if P = 8%)
Hibor rate mortgage plans and traditional mortgage plans each have their own merits. More and more people choose the Hibor plan because overall they may able to pay less interest due to overflooding of "hot money" in market that keep the Hibor rate at a low level. The Cap (upper limit) can safeguard the interest of those who choose Hibor rate plan when the Hibor rate goes enormously high.
Below is the site which you can see the trend of Hibor rate over the year.