I'm in the middle of trying to figure out whether to go 2cm or 3cm, and I didn't even realize that granite came in two different thicknesses until recently. I wish my fabricator had told me that I could decide because I just learned that the slabyard has both thicknesses available in the stones I'm considering. The funny thing is that I moved to So Cal from Connecticut about 5 yrs ago and have renovated kitchens in both places. In CT, it was never a question, I just got the 3cm and there was no laminated edge and conversely, when I moved to So Cal 5 yrs ago and renovated (yet another!) fixer-upper, no one ever asked which thickness I preferred, I just went to the slabyard, picked a slab and it happened to be 2cm. I never realized that there was a thickness option, or that there even was a difference. Duh!! What should've clued me in was that in So Cal there was a lot of discussion about which edge detail to choose. Because I had black honed granite in CT and like a simple, plain look, I chose the same when we moved to So Cal (and, to make matters trickier, at that time, plain black honed granite was pretty unheard of around here so I don't think the fabricator knew how to deal with it well). He asked me how I wanted the edge, and I told him that I wanted nothing fancy, just a plain eased edge....I was SOOOO disappointed when the counters were installed and I saw this thin seam running through the middle of the edge. I had no idea that they would put an edge over the slab and didn't get how that could happen. Of course, the fabricator, thinking this was standard and thinking I knew what I wanted, having done it before, didn't really explain and warn me strongly about the seam issue. For awhile, I couldn't understand what happened and what was the difference between the way my counters were made in CT vs. here in So Cal. Now I get it. This renovation (yes, we've moved into yet another fixer upper - last one!), I'll go with the 3cm, but from what I understand, I need to warn my cabinetmaker that I'm using 3cm because I've heard he needs to adjust the cabinets tp accept 3cm. That's another difference between east and west coast situations...in CT, the cabinetmaker assumed I was using 3cm, but here in So Cal, the cabinetmaker is assuming I'll use 2cm and needs me to warn him if I use the 3cm. Just something to think about for those perhaps in similar situations - remember to confirm the size of granite with your cabinetmaker, in case he doesn't ask.

With a mitered edge, the line tends to be hidden on the corner transition. Some of the quartzites are pretty expensive so the 3 cm might cost significantly more (though the fabricator will charge something for the labor of making a laminated edge and probably even more for a mitered edge so that offsets the extra cost of 3 cm unless you go for a 2 cm edge). Our quartzite is laminated, not mitered and the fabricator did a good job so I mostly don't notice the line. Only when I look for it. You don't need to do a laminated edge even if there is plywood under it. Two friends of mine did a 2 cm thin edge. One used a simple trim molding of wood matched to the cabinets to cover the edge of the plywood. The other left the plywood edge uncovered - I know because I put my head under the counter and looked into the shadow for it. If I was doing it, I'd probably cover with a trim piece because it would bother me, but only someone very TKO who looks for it would notice if you didn't.

"I have also been told that 2 cm is rarely used here anymore." and ..."oh, those over there are just 2 cm so don't bother looking at them." Not really. 2 cm is pretty much the standard on the west coast. I live in the very northern part of San Diego County and have been looking at granite for about 8 months. It turns out we live in Granite Yard City; there are at least 6 granite yards within 5 miles of my house and another 8 or so just 30 min. down the road towards San Diego. Lucky us, the closer ones seems to have a better selection. In any case, about 95% of what we've seen has been 2cm. The place I linked above is absolutely the exception in offering only 3 cm. In the end, our choice was made because we liked this outfit's work, not the thickness of the stone. There are benefits to each choice, but personally, I could readily go either way. I did see a 2 cm quartzite I loved, but it was pricey (!) and we would have needed 2 slabs to be sure there was enough to cut for the extra thickness on the edge. sigh The place we went with charges per square foot and they keep the leftovers. Had the quartzite people offered that, we would have seriously considered it. 2 cm or 3? Don't worry about it, just find one you like.

99% of all quartz manufacturers will not have 30mm in jumbos. You will have to go into the color you like and see if a jumbo is available on their site The four you have listed there are Jumbos available if in stock.