I use a Dell xps27 as my main machine. This is an all-in-one, so the components are the same as laptops. It's got a 27inch touch screen, but I don't use it as such very often. I just find that it's more convenient using a mouse.(It has an i7 4770S quad core processor and a NVidia GeForce GT750M graphics card). It renders poser fine. I've also got an alienware 17inch laptop. This has a more powerful graphics card (980M, 8gb) but I find the smaller screen means I don't use it as much. The poser ui scaling sort of works but sometimes I find bits I can't read. (the laptop has a 4k screen, the xps a QHD (2k) screen). In general you get more bang for the buck from desktops, so if you have space this is still probably the way to go. (I've just had my i9 machine delivered but haven't set it up yet but expect it to be significantly faster rendering.)