Mr Muscle is a brand that has been around for a good 20 years, trying to persuade us that the brand makes cleaning really quick and easy, even for weedy people. That is if we choose to believe the advert.
I was brought up very traditionally with a cream based cleaner, Windolene, being the way you cleaned windows. A bit of the product with lots of elbow grease, and you got great results.

The first time I came across Mr muscle glass cleaner was in 1998. I started working in a chip shop to help support me through university. When you had worked there a certain length of time, as well as serving I took on other responsibilities such as cleaning the shop in the quieter periods, so I suddenly aged 19 came across all these different cleaning products that I had never used before, and I started to form some non-parent influenced opinions.
In chip shops, there is a lot of grease and steam, which together are not a good combination. Anyone who has been in a chip shop will be familiar with the way the food is displayed in a glass cabinet. Customers come in, and touch this cabinet in the shop side, and it can get quite grimy.

I would be sent round to the shop side with a bottle of this cleaner and a cloth, and be expected to whizz round and make it look better in a short gap between customers.
Using Mr Muscle glass cleaner

This cleaner is in a trigger spray bottle, containing 500ml of the product. It is a green liquid, which is a little different to other window cleaner sprays on the market which are clear. A little does seem to go a long way with this in my opinion. Too much and your cloth becomes saturated and no longer works well.

A quick spray, a quick wipe and the surfaces are clean.
My opinion

When I was first using this I was so unbelievable impressed with it, as it would bring the outer surface of the food cabinets up really well with no smears and no product residue.

The first time I had to buy my own glass cleaning product, I opted for this because I knew it worked well.
However, in my own home, while it still worked quickly, I could not always produce the streak free finish I had experienced in my work place, and I was left disappointed.

Nowadays, I am still using up the first bottle of the product I bought 7 years ago, with at least 150ml of product left.
Nowadays, this product is still one of the best for cleaning my interior mirrors such as the one in the bathroom, but I do not use it on my windows as I don't like the smears that remain. The mirror needs a wipe so often that the annoyance is minimal.
Why did love turn to loathe?

Maybe not quite as strong as loathe, but I certainly could never get the results at home that first impressed me so much.
The only thing I can think of is that when I used it in the chip shop the glass it was being sprayed onto was warm, so therefore the very runny liquid cleaner evaporated really quickly. With hardly any effort the glass looked very clean.

Glass surfaces in the home are never as warm, so I was never going to get the same effect.
If my windows were exceptionally dirty, I might use this to get off the first layer of dirt, but overall I do not think these make my windows fully streak free. To me if I am doing a job I want to do it properly. I am all for saving time if you get the same end result, but this is a bit lacking to me.

I know a lot of people love this, and maybe I am a bit too fussy, but that is the way I have been brought up, and is the way I feel about it. I can appreciate it is very useful in a location like a food retail outlet as it leaves little smell and you can quickly get back to business without putting off customers, but I want a little more from something I use at home.