Disclaimer: I used to make a living selling countertops! No more, but just wanted to be up front!
I sold a product called Caesarstone, a competitor to Silestone, and Zodiac. These three are all the same product, from different factories. Breton of Italy has sold the patent to many companies around the world. These products have a uniform look, and won't have the movement of natural stone. Preference issue... The manufactured stones are non-porous, several times stronger and more flexible than natural stones, and carry 10 year warranties. They are very heat resistant but can burn (yellow)if you have a very light color and for some reason a pan that reaches beyond about 550 degrees (I never saw it happen!). This stuff is not going to help you if you drop a wine glass. It's hard!
Natural stone is beautiful, and unique. It is porous and can stain (especially the lighter colors). FWIW, Nat. Stone is not compliant in commercial food prep areas for this reason. Sealant about every couple of years is recommended. It is very heat resistant, but doesn't like shock (hot then cold). Cracking is unusual, but more likely than with manuf. stone. Never met a stone fabricator that would warrant the natural stone.
Corian is an entirely different beast. Non porous, warranty, but plastic, and can scratch. It can, however, be buffed and even repaired seamlessly. Stones...no way. It's hard to scratch 'em but if you do, it's in there. It'd take alot to resurface stone. Not usually done. Corian doesn't like heat (acrylic).
Ultimately, it's preference (of course). If you love the look of Natural, nothing man made comes close. If you're looking for the most durable thing on the market, the manufactured stones are incredible. If you go the manuf. stone route, check the above suppliers for color, they're all different!
sounds like a fun project. best of luck!
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