I'd not check photo gear if avoidable. I've done so with no issues, but only on a return from an international trip, CF cards and backups on my person, when a loss/damage of gear would not mean a loss of photo opportunities (gear is insured, of course).
Largest carry-on Peli is the 1510. Actually, I'd recommend the Storm equivalent (Peli bought Storm a while back), the im2500 - the latches are easier and quieter than Peli's 'knuckle-busters'. The only disadvantage I see with the Storm version is that the lock holes aren't metal-reinforced like the Peli.
Having the carryon hard case is a good idea regardless, in case you're forced to gate-check - that happens pretty often if you board in a later group on domestic flights, which are often fully booked (at least, on the routes I've been flying lately), and also sometimes on smaller regional jets.
You'll want TSA approved locks, else if you check (even gate check results in going to baggage claim at some destinations), non-approved locks will be cut. I use these SearchAlert
locks with my im2500.