There are a few threads on here about Crispi sizing now ... the search tool is your friend!
My experience has been slightly more complicated than the above: as every manufacturer's last is different, the best fit in different shoes and boots will often be a different size across brands and models.
More importantly, different manufacturers give different equivalent sizes across the UK, Euro, and US sizing ... so if you're wanting to cross-check, for example, your 'standard' Euro sizing with Crispi's (or anyone else's) US sizing, the lack of consistency across makers prevents this.
That makes it hard to say what my - and possibly many people's - 'regular' size is.
Having said that, I took all my shoes and boots and went with both the mode and median averages. For length, the Crispis are about right, although I'm yet to test them on a steep descent - I'm guessing that a half size larger would be a bit safer and prevent toe-slamming in the end of the boot. We'll see.
As for width, the 'wide' sizing that B.O. stock is just an EE. My feet are apparently only sightly wide, so an EE should, in theory, be too much. However, based on the reports I'd seen about the regular Crispi toe box being fairly wide, I went with the standard width to begin with. It turns out that these will be okay for short hikes, but on longer and multi-day hikes that flatten and widen my feet, the regulars won't cut it.
In my case, I'm outside the US, so am pretty much stuck with the first pair ... and had to order a second in the wide.
Short summary: I agree on the 'go with your regular size' - IF you have such a thing - or a half-size up, especially if you're doing a lot of ascending/descending. And don't place too much faith in the reports of the wide toe boxes - if you have even slightly wide feet, the wide option might be the best bet.
This, of course, is assuming you can't try them on first, like many of us here.
