Steve, I have a HP Multifunction WiFi printer which works seamlessly with my Macbook Pro.
Its a laserjet printer which although cost a bit more than an inkjet, the quality is fantastic and, although it may be a bit early to say, I think it may be cheaper to run. It felt like I was always buying ink for the HP inkjet printer but I've had my new printer since the start of January, I probably print 20 pages a week (so very light usage) and below is my current ink status.
As you can see, it is very frugal....think of a Laserjet as the 335d to your RS4 Inkjet
Of course, when I do need new ink it costs £100 per colour but it seems at my current rate, I won't need to replace ink for over two years!
This is the printer (HP M175nw) and I can confirm that the cashback offer works well making it very good value for what it is. Oh, you can even print from anywhere - the printer has it's own IP address so you can connect to it from your phone or tablet....although I personally have never found use for this feature as I've never needed to print something that I didn't need at the point I've printed it!