Mostel
4360
I've owned both
The Daytona, while very nice, is a scratch magnet of epic proportion. I've never owned any watch that was so easy to ruin, as it were. The tiniest brushes will leave a mark.
But these are not the good marks of character--these are marring scratches that happen too easily on a very, very, very shiny watch.
OK, it's a great watch anyway, in every way. But I sold mine and no regrets at all.
One great things about a Daytona is how relatively thin it is, while almost all others in this class are FAT.
The XXI is FAT. 15.2 mm thick! That's thicker than an AP ROO!
But I really admire the Breguet and have recently considered buying it again.
Why? It has a very rare outside minute counter. So it is really practical, legible, genuinely uselful. A true chrono, NOT in name only as so many are.
The dial is a work of art on many levels. Spectacular and original. Details, details, details, but not busy.
I would only get the RG version if I did ever buy this model again, because it is beyond-stunning in RG. Yet still very, very sporty.
And it has a DATE! Beautifully rendered, not an afterthought.
Downside of Bregeut is disastrous resale value. You better love it or buy it pre-loved.
Good luck!