Hi all,
I'm currently 450D owner and I think that after 4 years it's time to upgrade. I'm mainly shooting portraits / street / gigs / DJs / low light / strobist.
My current gear ready for FF:
I already have 3 primes: EF 28 f/1.8 USM, EF 40 f/2.8 STM and 85 /f1.8 USM. Flash: 430EX II and triggers Cactus V4 and Pixel Kings for TTL. I also have Vivitar 285HV.
My friends can borrow me EF 70-200 f/2.8 L IS USM, EF 70-200 f/4 L USM and EF 24-70 f/2.8 L USM - so zoom is not a problem when needed.
My options:
1.) buy 5D classic - I've read a lot of posts here and there - it has a really good reputation in terms of color and image quality even nowdays. AF is old but 5D Mk II has the same so no difference - when I need I just attach 430EX II for AF assist. Really important question is: how it is at ISO 1600 and 3200 ? I'm using my 450D at 1600 and do some post to correct noise with good results. I'm fine with 12 Mpx. Also used price is around 600 Euro.
2.) buy 5D Mk II - I'm sure it's a great camera. I've shot with it on one Canon event and was pleased even with photos at ISO 3200 and ocasionally at 6400 (always depends on actual situation). I know what this cam is capable of in terms of both stills and video. AFMA is a great feature becasue I'm a prime shooter. AF same as 5D as I mentioned before. There is also a possibility to hook it with Magic Lantern. As I've said before I'm fine with 12 Mpx.
3.) buy 5D and rent 5D Mk II when needed - until 5D Mk III price drops to affordable level...or some lower specd FF body will be announced.
My preferences and question for you:
I really want to upgrade straight to 5D Mk III, but the price is ridicolous (at least now). It has all I need/want from camera. I also want to keep the new cam for at least another 4 years (so I think that buying 5D Mk II is not so wise decision - reason is obvious = price). So what I'm really looking for now is your suggestion for the best temporary setup. What do you think ?
Thanks in advance 
As someone who use's the 5Dc alot, I can say its IQ is still better than any APS-C camera canon makes. You will see a huge difference jumping to FF from crop.
Its ISO performance is still good, I've used all of its ISO settings with good results. Its H level or 3200 ISO is a bit limiting but still better than my 7D.
You can find them around 700$ on the used market, but try to get a body that was a back-up unit and make sure the mirror fix has been completed.
You can use it until you have the dough for the mk3, then sell the 5Dc for almost what you payed for it. You could buy two 5Dc's for the price of one MK2 if your shooting all primes. (which I also do)
Even better, you can buy the EG-S screen to see DOF thinner that 2.8. An advantage that the MK3 doesnt even have.