unless it is a leaking(defective) kayak, i don't see why water would come in under normal conditions. we kayaked several times in the creek and the mallows bay. didn't get wet.
Supply chain
if you scroll down to read the info, there is a table with all the info you need and that table shows the comparison between diff. models. it says max. 300lbs. i would play safe to go 275lbs.
I ordered mine on July 16th and get it just under two weeks later. Would've been great except it had a huge gash in the bottom and the delivery guys had left before I noticed. If I were you I would ask them to wait so you can look it over ...