The O.S will balance the plane w/o nose weight! But iam going to want to be able to fly 3D with the plane! So a i think bigger will be better although as you said i will suffer a weight penalty! The OS is the suggested engine for the plane but i am thinking that it wont really have enough power and dont want to spend £1000 on having a plane which cant do what i want!!

Thanks for your help every one! Are there any other engines which would do the job, the lighter the better!!

Rob