It may not be nostalgic for other people but this game brought back memories of going over to my friends house in 3rd grade and playing his dads games in the downstairs computer room they had. While I may not have played as many clunky 3d games from this era however, if you were to simply change the perspective from first person to a side view, you'd have most of the front page of most online flash game sites in the 2000's. I couldn't tell you how many hours my classmates and I pumped into flash games from grades 2-6. Beach Defend certainly recaptured some old childhood memories.
I especially like the lower res title picture, that alone almost places this right along side games I could find in my dads collection gathering dust on an old bookshelf.
The graphics themselves evoke the likes of old flight simulators and racing games. There's just the right amount of 3d mixed with 2d sprites for it to feel like the devs (if this were made back in the 90's/2000's) wanted to make the game detailed, but computers couldn't handle it and they didn't have the budget for it.
The gameplay itself is exactly as advertised, you defend a beach with a machinegun and missiles, simple but it works. And I loved the microtransactions and was surprised that you went so far as to actually make a website for it. The amount of effort put in is obvious and it paid off I think.
Unfortunately my laptop doesn't have a CD drive so I can't test out that part but it sounds really cool, good job man!