Do you absolutely, positively gotta have it now?
If so, the Squadron price is probably pretty good. You may check some of the other online shops, Great Models, Sprue Bros, etc. and check price, shipping costs, and availability.
I'm planning on holding off for 6 - 9 months. I have enough in the stash to keep my interest and I'll see if the kit ends up being discounted (such as the Revell U-Boat did at Hobby Lobby - where I got one for about 35 bucks). Then the cost of the aftermarket items don't seem to hurt as bad.
The choice of now or later is entirely up to you. This kit will likely remain in production and available for a long time.