If you have an URNU unit near you, apply for that! It's a lot more student orientated and would suit most students better than the Reserves. You'd get to go on their P2000 patrol boats, go on exercises etc whereas in the RNR, you'd spend the first period (can't remember the exact time scale but over 12 weeks) in a classroom going through the task-book. After that, you'd then have to complete basic training and then continue your branch training at the unit. So if you actually want to be hands on etc, I'd go for the URNU!