Well i've built her. Not too happy with the fitting issue not very severe though. I'm used to build better fit models of Tamiya. Newer Revell's mould is lookin better though. Guess they learned.
My suggestion: Be patient. And drill the free flooding vents/holes especially those above the waterlines. It really adds up to the realism. Better to endure a few weeks pain of having to drill those holes than to have a toyish look to the built model. Besides you've spent some money on her. She deserves the best effort . And you will earn for your sweat/toil in the end. Believe me.
Oh yea, research the sub, look for real pic of the sub in color. And look for some amazingly built model just for reference. If you are planing to add the rust effect you need to know where to apply them. Be careful as this may actually destroy/damage the realism looks of your boat if not done carefully. Too much is the customary habit for beginners. Color of the upper hull and lower hull is everything. Pick your color carefully. Look at rokket site lots of useful info on coloring the boat. Good luck.