I've got the Spec1R-Extreme Fabrizio/Cathedral. Also an Arai RX7 and a QuantumII.
About the Suomy:
Graphics and paint quality: top notch.
DOT sticker: better stickers on bananas.
Beyond the paint: fit and finish aren't as stellar as paint would lead you to believe. One of the snaps that holds the lining to the shell has never stayed snapped. Liner is comfortable (I bought into the alcantara), but not as nice as either of the Arais. Strange chin strap snap; integrated plastic piece sticks way down -- hard to explain, but looks like a tongue depressor hanging out of the bottom of the helmet. Venting works, but vents seem to have been added as an afterthought. Flimsy control in the center-top, no controls on the top-sides. Vent under visor pretty cheap. Big visor, I feel there is better peripheral than the Arais. I understand visor finish is very fragile; I've only used water and a cotton t-shirt for cleaning. No windex, plexus, or paper towels. It still looks good. Venting is no better than the RX7, but helmet is noisier. If you wear earplugs (I do) it won't be an issue.
I get more comments about the Suomy than I do when I wear either of the Arais.
Overall, I don't regret buying the Suomy and I still wear it regularly. But my favorite is still the RX7. I wear XXL Suomy and XL Arai.
Can't comment on the Shoei, but I'd love to try a Lawson.