Upload & Sell: Off
I mainly shoot with MarkIIn bodies - sports. I bought a 7D for some high ISO static shots and a few times used it to cover action. I've also used the 5D2 for sports once.
I can say that the 5D2 is pretty decent for covering action, but it doesn't have that "be ready NOW" to take a shot when I depress the shutter button.
The 7D is definately an improvment in responsiveness, speed and extra reach with the crop sensor, but it is still only about 75-80% of what a Mark2n is. I'm sure some of it is having 5 years of history with the Mark2n bodies, knowing which functions will get me better results - some of which the 7D simply doesn't have.
I believe any camera can yield satisfactory results, once you know it's limitations and work around them. With the 1D series, you have so much more flexibility in 'programming' it, that you get much better results that much easier because it has the algorithms to drive the lenses more accurately.
Limitations of the Mark2N:
- older display screen, compared to the 7D, images look dull and soft, but are actually just as sharp or shaper when downloaded
- high ISO limitation, but you know this and have other options. I'll use 1600 all day with a little NR and 3200 when I have to.
- some 'personal' functions have to be activated via FW cable and software - not critical ones, but alot of capability is has and can utilize, aren't readily accessible to the user unless first set by software.
- Near EOL expectancy. I think the MarkII just got the axe from CPS repair on the last go around, I would expect the IIn to be dropped shortly. However, they're built like a tank. I commonly go through 300,000-500,000 shutter actuations PER YEAR on each of my bodies, maybe having a shutter failure prematurely 1-2 times in the past 5 years (otherwise, I pre-emtively repair them every year... after 300,000+ shots when I have some downtime.)
I think a MarkIIn would be a great addition to get your sports coverage well covered with minimal frustration of missed shots. Like any technology, as you know, it's not going to be a 5 year investment camera, but once you get hooked on 1D performance, you'll have your sights set on a 1D-X next year!