Apologies for double posting, but realised i forgot to mention the finance- i have written it so many times now on TSR but the 4 year course is soooo much cheaper. You don't get student loans for a second degree so the 5 year course will cripple you, £3000 x 5 = £15000, plus no help with money for accomodation etc.
4 year = £3000 fees first year, years 2,3,4 paid for you by NHS. Also NHS give a bursary which (don't quote me on this) is a few hundred pounds a month in years 2,3,4.
In short, if you can get on the 4 year, then do it.