I have had 4 of these 3 were useless. The first two plugged into my laptop just difficult to see in daylight.
The third was a $50 unit from Amazon with a terrible screen. The most critical bit seems to be the angle of view from the probe and the depth of field. Some are good for looking down your ear. some for your teeth but I wanted one to look inside the sump/inside the sills to check on my waxing treatment etc .
This model called a P100 was £25 ..$30 and seems to have it all right ,clear colour screen ,right view angle DOF and that important stiff cable . Does not record video or store imaged on memory card .From ebay by multiple seller.

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P100 with 2m cable

 

For less than $10, you can get an endoscope/borescope off ebay that works with a cell phone. I paid about 10 times that much for a Harbor Freight borescope and the image is larger with much higher resolution on the cell phone, plus, you can enlarge the image and search around as if with a magnifying glass. Last summer, I scoped out our nephew's (Wards Automotive CEO) Audi and verified scored/seized cylinders from overheating.

 

The cheap ones only work with Android and mine is an apple phone.
The Bluetooth ones are $25 in UK .
Then of course, if you buy blind you have to hope the lens /DOF etc is what you want.

 

Ask around for an Android and someone will give you one.. Don't know about the UK, but like millions of others in the US, we recently had to upgrade to 4G and have a pile of excellent, obsolete 3G phones. I set aside an A1 out in the garage for borescope, oscilloscope, calculator, mini flashlight and OBD tasks as it is better than my current 4G phone and if it breaks, no loss. Speaking of loss, I lost my current phone for a couple of weeks as I used it in wife's Crossfire for OBD scanning and forgot where I left it.

 

I have boroscope attachments with two head sizes for my Autel MaxiSys Elite (not cheap), but I recently saw a YouTube video in which this Sansisco unit was demonstrated and the price was low enough that I decided to grab one as a cheap backup:



My initial impression is that the image quality is quite good for the price and the display size is two or three times larger than my old backup, a Milwaukee pistol-grip style.

The controls on this Sansisco don't seem to be quite as intuitive as I would like, so I had to consult the instructions (who wants to do that?).

Apparently some of their models come with the option of right-angle view, but this unit doesn't seem to have that. My Autel endoscopes have little mirror attachements for viewing, for example, the sides of cylinder walls and valves.

Otherwise, this seems to offer a lot of bang for the buck.

Cheers,

Don