I am planning to pay $2k and put the rest on a lease plan, wondering if i should go for 2 or 3 years

technology goes so fast, i worry within 3 years FS100 becomes very outdated when 4k become standard

but be honest, I am still mainly give DVD to most of my clients now.

NTSC Video was standardized in 1941 with about 500 lines of resolution. HD television was standardized 50 years later with about 1000 scan lines. Assuming an exponential rate of technological progress, 2000 scan lines might become a television standard in another 50 years.

There will always be something new, something better (a relative term) and "The Next Best Thing".

If we all buy into it, then we are always behind the 8 ball money wise and the manufacturers get rich while we struggle to justify our purchases.

I don't see 4K becoming the "standard" anytime soon and dvds will be around for a long time yet.

If it were me, I'd have no problem going ahead with the plan you have to go 2 or even 3 years with the camera but if you want to feel more comfortable, go 2 years, see what the new next best thing is, if it's something you need to have to continue to make a profit in your business and then you can decide based on information and fact what you next move should be at that time. Since no one has a crystal ball to be able to read ahead into the future, that to me seems like a logical plan.
Your choice.

I would ask the question differently: How long before this camera pays for itself? Will I earn more money because of it? Will it open up new revenue options for me?

I'm still getting use out of a Sony DSR-390 that is 8 years old (and SD to boot!). It paid for itself in the first year of purchase. HD tech is more volatile than SD, so I wouldn't expect 8 years of use from ANY camera purchased in 2012. I'd be glad with 3 to 4 years of use.

Rather that worrying about what's around-the-corner (4K, 8K, 3D, etc), I'd just be concerned that you can generate enough business to offset the purchase before it outlives it's usefulness. In other words, you need to calculate your ROI.

What is more likely to be a decision factor in this class of camera is ND filters. I think what prevents the FS100 from totally dominating the under $5k market is its lack of ND filters which is a Don't Care for some but a strong negative for others. From what I have read, it's a product of some fundamental design decisions of the camera and that adding them is significant.

That said, if a new model came out that had ND filters, it would probably be a price increase but you may find a deal on the current model.

all things considered = 3

I use adjustabel nd filters like singh ray. A bit of a pain but they work great.
Bruce Yarock

I agree with Oren's assessment. "How much are you going to make with it?"

My guess is that if you get a signed up with a long term project that requires 4K, (considering you can rent a camera for a one-off project) you'll get paid enough money to buy or lease a better camera.