Hi,
I did a BSc in Biochem and took a year out before my Phd. It depends on your state of mind whether you'll benefit from time off. For me, I just needed a break; time away from the lab was good because i spent the year travelling and temping. From part-time teaching to data input- it all helped decide that a Phd was something i definitely had to do and made me more motivated to do it. The experience you gain and wider perspective can impress at an interview, a year on.