jwn Loc: SOUTHEAST GEORGIA USA

what kind of sport?? I drive a shuttle for the PGA event here on St Simons. The professional photogs (network & print) I drove around that were using Canon had the 5div and 1d , didn't see any 7d. That being said the had the variety glass for all situations.

amfoto1 Loc: San Jose, Calif. USA

7D Mark II is a much better choice for most people, for a sports camera.

Full frame is not necessary for most folks and will require you sink a WHOLE LOT OF MONEY into much bigger, heavier lenses.

Yes, the pros use FF cameras for sports (20MP 1DX II, 22MP 5DIII, 30MP 5DIV)... but they have virtually unlimited budgets for lenses or employers who buy their gear. They also have as assistants and/or golf carts to haul around big, heavy gear such as 200-400L Teleconverter, 400mm f/2.8: and 600mm f/4L lenses... as well as press passes to get closer to the action. The $3000 to $5500 for the full frame camera itself is just the start... Also plan to spend upwards of $10,000 to $20,000 on lenses.

My full frame camera gets used for landscapes, some portraits and some macro. Not for sports.

For sports, I use a pair of 7DIIs. Much more practical and more than enough image quality for the vast majority of purposes. Unless you're a highly paid pro and/or your employer buys your gear for you... and you've got a helper or golf cart!

Sigma 120-300mm f/2.8 would be fine for Hockey... In fact you can often use even shorter focal lengths (70-200mm) because shots of hockey often aren't as tight and you can usually get fairly close to the action.

But 120-300mm is not going to be long enough for baseball. Even on a 7DII you'll need at least a 1.4X.... or quite possibly a 2X if you want to get shots of the action deep in the outfield. With FF camera, better save up for a 600/4 or 800/5.6!

SharpShooter Loc: NorCal

Don, the 1Dx I bought had 185K on the shutter, that was pretty low for what I paid. I wanted to stay in the 200K range. At 200K a 1Dx has MORE shutter life left in it than a new 5DmklV!! They are rated for 400K.
The cameras are very heavy duty, not for the faint of heart. They are big and heavy compared to all the Prosumer cameras, like a 5DmklV. Many people are taken aback by their size and weight! NOT for those considering a 4:3! LoL
They do produce very beautiful sharp and saturated images with good noise control.
I also don't usually use the FAST frame rate, only when the timing has to be perfect.
My favorite feature is spot metering using any single focus point I assign to it. It can produce a perfectly exposed face with no shadow but the background might be blown out!!
I think the 100-400 is too slow for ANY indoor shooting. You'll have to have the ISO pretty high. F4 is usually to slow! Good luck!
SS

Cheese

I had the same decision to make. I rented the 5D4 and have never looked back. I still have the 7D2 but have rarely used it since getting the 5D4.