Pentax Q 06 Telephoto
Its difficult to talk about a lens for the Q series of cameras without also talking about the cameras. Even though the lenses are interchangeable, more than any other camera system the two are intrinsically linked. What I mean is that you really can’t talk about one without the other. So while the 06 telephoto is equivalent to a 70-210mm lens on a 35mm format camera it really isn’t the same thing.
The sensor on the Q7 is tiny and that has drawbacks and advantages. The drawbacks are around noise and a very large depth of field. Using the 06 addresses those issues somewhat by being relatively fast at f2.8 across its entire zoom range and also with the longer focal lengths it is possible to isolate a subject against the background. The small sensor also allows for the lens to be built incredibly small, in fact it only weighs 90g
45mm f2.8
The lens renders the out of focus areas in a nice smooth way leaving the point of interest to stand out effectively. The ability to focus closely is limited though at 100 cm throughout the zoom range which places limits on how large you can reproduce an item, it is no macro lens. Also on the detrimental side of things the small sensor of the Q is prone to purple fringing and moire, the former can be mitigated in editing but high contrast areas can be challenging and can require a little editing or profiling. Also there is a tiny amount of chromatic aberration that also requires addressing to achieve the best results. This despite the fact that the lens is built with 14 elements in 10 groups. 
45mm f3.2
Of course you don’t always want a shallow depth of field and for that the Q and its lenses excel. Also stopping down can improve the image quite a bit particularly for distant details.
So once you consider the limitations and if you work within the abilities of the combination you can get pretty good results and when you also consider just how small it all is the 06 zoom is a great little lens worth having for anyone with a Pentax Q series camera.
29.7mm f4
The Pentax Q 06 Telephoto does provide excellent sharpness across the entire frame as seen above, you can click trough to a full resolution version of this file.
One final note this lens as well as the 01 prime and 02 zoom all have a 40.5mm filter size so can share filters and also lens caps. You can just grab any one from your bag as your changing lenses.