I've done the Belfast -Liverpool route many times in a single, and I agree with the advice in the bove posts, especially re immersion suits & plb. one thing i would emphasise is to go high. There is a class D airway from iom to belfast wich you can access without an IR. I knew that I could always glide to land in the SR20 from FL100, which a typical PA28 can easily reach. I accept though that as a newly minted PPL the cloud cover would be an issue for most of the year. IOM to Wallasey is of course a different prospect due to the Class A. Once you are IMC capable crossing the Irish sea on top of an overcast is great fun with the Isle of Man no more than a ripple in the smooth white deck.