I've owned either kind and all comes down to personal preference, personally i like that it saves space and considering im touch type i've never used the num pad, so why star
Will typing position be disrupted by the missing numpad?
There is also the ergonomic issue, how tenkeyless will allow me to put my hands closer together. I'm not a small person and I don't feel stretched with my 104 keyboard ATM.
Soz if i've missed this reading through the posts... I've not measured it but comparing the two types of keyboard side by side, the dimensions are the same... think of the Tenkeyless as a normal Keyboard and then "saw" off the numpad... basically regarding ur questions it shouldnt affect you