go with a kit if its your first pond.remember Bigger is Better!most people redo the pond after the first year saying "its just not big enough". if you have the room go with at least 1500 gal. that will give you 1 or 2 koi and 5 comets.the signature series is the best ive worked with.
http://www.aquascapedesigns.com/prod...s.php?catid=36
it might cost a few dollars more but well worth it. good luck steve