Switching case, moving pre-installed PSU

So, few years back I bought a Cooler Master Cosmos full-tower. Can't remember the exact model name, think it was the 1000. It came with a pre-installed 850w quality( I think?) PSU which has always worked nicely. Anyway, I'm moving to the city now and the case is simply too big to comfortably fit in the apartment, so I need something new and somewhat smaller than the huge and heavy Cosmos.

I've been thinking about the CM 690 II for a new case, but it doesn't come with a pre-installed PSU. Since I don't have the Cosmos here with me, and since I need to order the parts before I'm in a position to check the Cosmos, I was wondering if you guys think it likely I'll be able to move the PSU over to a new case easily? I assume there'll be no problem, but I need to know for sure before I order.

Also, if there are any case recommendations beyond the 690 that would be welcome. I like to have decent hardware, but I'll never run SLI/CFX, I'll need at least 3 SSD drives and probably 3 HDD drives as well, and I'd place sound/cooling about equal. It shouldn't be bigger than a mid-tower, but it needs to contain one of those somewhat tall'ish Thermaltake CPU heatsinks( think it's around 140mm, with a 120mm fan).

I would think that the PSU should move over no problem...

As for cases - do you prefer subtle clean designs or are you looking for a more gamer-style model?

There are so many...

No special preference there really. Primary focus is good cooling/acoustics/size. Just had a look at the Nanoxia Deep Silence 2, which seems to fit my criteria fairly well. Any experience here with that?

It's brand new, and no Nanoxia cases are yet available in the USA.

The reviews have been very good - but I'd get the Deep Silence 1 as it has more features and excellent reviews.

My next case will most likely be the Fractal Design Define XL R2, just released and scored even better than the Nanoxia in testing - it is probably too large for your purposes, however, so take a look at it's baby brother - the Define R4.

Yeah thanks, might just go for the R4. Bit heavier than I'd like, but other than that it looks excellent.