I have used both Makeplayingcards.com and also printerstudio.com
Interestingly, the address on the package was the same for both companies, so the printing is done at the same premises.
Both were excellent.
I have printed shedloads:
cards (extra large sized, minis, poker, bridge - linen and plastic cardstock)
Wristlets
Mouse mats
Coasters
Place mats
Door mats
Journals
Dog tags
Only had one minor problem with quality on one deck which wasn't major, and they immediately offered to rectify.
As has already said, decide on what size you are printing, and who with before getting too far down the road with artwork. It is easier to use the template for your artwork, knowing it is right and will look in proportion when uploaded to the print site, than try and shoe-horn a design into the required template size.
Also, I can add a bit of info regarding the printerstudio 'stuff' as I have used them the most. They ask you to allow a bleed area for any slight alignment issues when it comes to cutting the images. I would say they are very good, and everything is pretty much centred. I also LOVE the plastic cardstock which is expensive compared to the linen. (Maybe something you can treat yourself to though
) It is perfectly flat, the colours are terrific and it is totally waterproof. It will take anything I throw at it.
Hope this helps
Davina