When interest rates are so low, it's hard to find somewhere that pays anything like a respectable rate.
These are doing a regular saver account, 3% fixed for 1 year, plus a 3% bonus (as long as you make no more than one withdrawal). Wopping 6% gross ! After a year, rate switches to variable but 3% bonus remains.... sounds like a good deal to me.
Max you can put in is £250 a month, but the amount you commit to is not fixed.