Label printers are great
I have a different (cheaper) model of Brother P-touch label printer; mine has the keyboard input but no USB socket for connection to a PC. I bougth mine for about 30 pounds when it was on sale in a shop a few years ago. There are many practical uses for the labels from such printers, especially if you use a narrower label tape (I think I normally use a 9mm tape). Here are my most common uses.
Print labels saying "TV", "radio", "lamp", "computer", "speakers", and so on, and stick these on all the plugs in your house. You will then never accidentally unplug the wrong piece of equipment.
If you frequently print and bind documents with a plastic-comb binding machine then print the name of the document on a label and stick this on the spine of the plastic comb. It makes it much easier to find a specific document on a shelf-full of bound documents.
Print your email address and mobile phone number on a few labels; some label printers can print two lines of (small) text on label tape, so such labels can be quite compact. Stick these labels on pieces of luggage that have a hard-case, on your laptop computer, on gadgets and so on. If any of these items get lost then the finder will have your contact details to report it.
Print in large letters on a (wide tape) label a message like "No free newspapers, leaflets or catalogues" and stick that on your letterbox. It will eliminate a lot of the junk that you would otherwise receive.
I agree with the manufacturer's claim that the labels are very durable. The label attached to my letterbox has been there for several years without peeling off or showing signs of weather damage. Likewise, the contact-details labels on my luggage are still intact (unlike the countless luggage tags that I had used previously).
Here are some other tips. If you buy a machine without a power adapter then don't bother buying a power adapter separately. Just run it off batteries. The first set of batteries in my machine lasted for several years of occasional use. The machine turns off automatically after being idle for several minutes, which helps prolong the batter life. The recommended retail price of the label tape is a bit expensive; typically about 10 pounds or more for one tape. Whenever I am running low on labels, I hunt for bargins on eBay.