I probably can guess the answer but I wanted your opinion about putting gear in checked baggage. I've done the same thing as you and the others for years but recently purchased a portable lighting solution - two Quantum X5d-R heads and corresponding QpaqX power modules. I wanted to have the ability to go to 400 watt-sec for each light for maximum flexibility in a truly portable solution. I'm thrilled with it so far. So... I went out and got myself a Storm Case in zonker yellow. LOL! This is almost identical to a Pelican 1620 in size. Ok, I know <grin> but my reasoning was BECAUSE it would be noticeable and I'd be more likely to see someone carting it off at an event. Frankly it would be empty at an event anyway or locked up in a trunk if I weren't using the lights.
However I planned to fly with this kit. I just received the case and it fit everything perfectly but went over-weight. Ugg! I have my lights, two nano stands, a Hakuba carbon fiber tripod and a lightweight backdrop. I guess I'll just go out and get another smaller case to split the load up. Again, I'm just interested in anyone's input as to whether they'd risk this kind of gear in such a case. My thinking is this sort of thing would not be as tempting as a camera body and lens and most wouldn’t have a clue as to it’s real value. Certainly doesn’t LOOK as expensive as it is. <grin> My camera bodies and lenses will obviously be with me on the plane. I've traveled a lot for my IT day job using a Pelican 1620 full of computer equipment and never had any issues with theft. I use two Pelican TSA locks and they often get opened up but nothing has ever gone missing. Maybe I've just been stupid and lucky. I figure as long as I have the stuff insured and I'm carrying on the minimum I need to get the job done (body, cards, two lenses and a 550EX) I should be ok.
I have a Peli case and I just love it...one of the best investments I ever made for
camera gear protection...when said gear is within my immediate control and possession...
I would NEVER though use it for air travel...it may be water resistant, it may be dust resistant, it may offer first rate impact resistance, it may have a "you break it we replace it" warranty...
But I refuse to put my gear into "checked baggage"...and by "gear" I am referring to body and lenses...
Those items go in a soft bag which meets the carry on requirements for size...and the Peli stays at home.
I guess there would be nothing wrong with checking in your empty or nearly empty Pelican case/s with an ATA approved lock on it...and maybe some less valuable accessories in the case/s...
As mentioned however these cases SCREAM-STEAL ME!!!
For my purposes, the case is a mobile "vault" of sorts that offers impact/water/safe storage benefits...and it sees all travel EXCEPT AIR...and then I make it a habit to keep it out of sight as much as possible, and always within my immediate possession and control.
If you intend to put your 5-6 lenses and DSLR and accys. into one case you WILL need a BIG one with wheels...or two smaller ones...I find that one DSLR body and three lenses are about the limit for the Pelican 1550 model (one body, a 24-70 f2.8L, a 70-200 f4.0L, a 50 1.2L and a spare battery and charger and a couple other very small items). That arrangement gives comfortable room between items without overcrowding. Your experience may vary...
Whatever you end up with...I would suggest that you take your gear with you when you shop so you can trial fit the gear you have and make sure it's going to work out for you.
When I internet searched for the Pelican, I thought for sure I would end up with a 1400 series case...but when I actually took my gear and placed it onto the foam I quickly realized I was going to have to go bigger to allow the distance I wanted between lenses etc. AND to get the depth (top to bottom) I wanted for the DSLR body...and ended up with the 1550...
I wouldn't know what size to suggest if you are going to get one case except to say it's gonna be BIG for what you described...
I will hazard a guess that a pair of 1550's would hold your 5-6 lenses and one body with some accys...you might be able to "double" the 1550's exterior dimensions to get an idea of the size of a single case...
HTH
Cliff