There a quite a few technicalities about printing that i've researched, but i'm still quite unsure of. I guess this isn't exactly krita specific.

I know things like, type of paper could change quality of print, or to get a better a print its better to use a monitor that's properly color calibrated (which can be expensive, so better to do it at a print shop)

My issue is really RGB vs CMYK, its come to my attention that most printers these days, although still using cmyk inks, actually recognize RGB colourspace? My understanding of this, is that the printer can recognize a wider gamut of colour. So does this give the printer more leverage to get closer to what is seen on screen, where as setting it cymk limits the amount of leverage?

I don't know if there are any colour print experts here, but is my understanding correct? I think the Krita crew have printed stuff for conventions, but don't know far they dug into that whole thing.

A lot of print shops use photoshop for their calibration too, but perhaps thats not such an issue if you are loading printer profiles.

1). It's not about colour callibration(which is you changing the contrast settings on your monitor) it's about colour profiling(which requires an expensive device called a colorimeter). The ICC profiles and LUTs(for OCIO) generated by that device can be used to have some similarity between colours from your printer and on your screen.

2). all CMYK profiles are device-dependant. Which means that you should ask your printer for a profile they work in. This also accounts for 'printers recognising rgb space', it's not that Printers recognise rgb space in genuine, it's just that they've gotten good enough to encompass the sRGB space(which is the default assumed for computer monitors) with their own device space, which makes conversion easier. There is no raw cmyk in krita.

3). It's best to use a 'working' colour space to make your files in, such as Adobe RGB(we install adobe-compatible and Clay-elle profiles that can be used instead of adobe rgb), with you file in that colour space, you can either convert it to the cmyk profile of your printer yourself, or you take the working space file to the printer, so the operator can convert it for you(they know the device the best, so it's not a bad idea to do this). The point of using a working colour space profile is so that Krita can do proper colour maths, as well as that you don't limit yourself to your current monitor's colours.

4). When converting, use 'relative colorimetric' for most jobs. 'Absolute colorimetric' for jobs that need exactly the same colours. And 'Saturation' for jobs that require the saturation to be maintained(such as infographics or advertisement).

tl;dr: Don't just randomly take the installed cmyk profiles as gospel, get one from your printer.

Further reading:
http://codewideopen.blogspot.nl/2009/12/inkscape-should-not-support-cmyk.html
http://codewideopen.blogspot.nl/2010/10/inkscape-does-support-cmyk.html
http://ninedegreesbelow.com/photography/articles.html<lot of articles, but they do give you a grasp of what is involved with colour management.

thanks a lot, i'll have a good read once I get some coffee in me.