I had the same issues exactly with my left Joycon, you know you can order the parts to replace this from ebay for about 3e but you do need the Nintendo tri wing screwdriver to take it out and a very careful hand. I have IT support training so it wasn't much of a bother for me, but if you've not replaced innards of something before it could be a little tricky, the thing is the replacement stick costs about 3e the replacement joycons are about 40 euros, it was a no brainer for me to try a repair and mines been working perfectly since.

https://www.amazon.co.uk/perfk-Joystick-Controller-Replacement-Screwdrivers/dp/B07DHP5VV9/ref=sr_1_13?ie=UTF8&qid=1536037708&sr=8-13&keywords=switch+joystick

There is the joystick and the screwdrivers to replace it for £5.99 but you'll wanna watch a video on youtube first to see if you would be okay with doing it, you need to release a number of ribbon cables inside the joycon to get access to replace the stick and they are tiny. Let me know if you want any advice on doing it.

Ive not had a problem with mine

That's an interesting issue. I haven't heard of that. I usually keep my joy cons attached to the device in it's protective case when not in use...mainly so my toddler doesnt pick and drop the system. I guess it is a good thing that I have been keeping it on the case if dust causes trouble to the joy cons.

So it is a common thing...I'll be wary of the dust issue then. Hopefully it can be avoided.

Yeah I guess eventually I will be nabbing an official one in case the third party one dies. 

Aye I know what you mean, since I got the Switch my PS4 and even my PC have slightly been retired for gaming since I just have it right there as my home system then pick it up outta the dock when I wanna head to work or travel away, found myself on flights for a long time in the last year and a half and each flight is a dream when I can just pop on headphones and game like I was at home with the little beast.

As for the joycon ghosting issue, I think that was something which more impacted early Switches, which would explain one from last may getting it as well as my one which was from launch window, if you look at the joycons you can see that the part under the stick isn't solid plastic but actually a very thin lair of plastic which you can run a fingernail under and lift up to see the innards of the stick slightly, the issue some people think is that dust gets under that cover and makes the stick ghost around the place, there are a lot of videos on how to clean it but after trying fine brushes and compressed air I just bought a replacement part and done it that way for myself, took a steady hand and about 3e worth of parts from ebay but all good now again.

Haven't really tried ordering from those sites yet as the shipping and tax are a huge concern for me especially where I live, but I might check my local online shopping site, though the problem too is that I saw how they open the controller and I know it's not as easy as when I was opening PS1 controllers, really afraid of destroying the thing as a result, but will try to open it if I get the funds for the joycons first just in case.

they are really really a ton of parts and ribbons inside this, tearing any of which (bar the stick you're taking out) will mean the controller is pretty much dead, but the thing with me was, I had 2 choices, buy a replacement or fix it, and since the "fix it" option cost me 3e (I already had the tri wing for opening retro carts) I really wasn't going to be losing too much by trying that first, heck if I ripped it and had to bin the controller I was going to be down 43e instead of 40, figured it was worth the gamble.

Here's the video I followed to replace mine, you'll wanna watch it before you even consider buying the part as if it looks too complicated to go into you are better off just to go for the new joycon or ask someone you know who is good with tech/very dexterous at small fixes.

I think I might end up buying a new one, and thanks for the video btw, I might do some tinkering with the old ones for practice.

you could always buy the new one, then buy that kit if you can get it there cheap later on down the line, I'm not sure about import taxes but obviously if you've bought online you know where to avoid getting caught out yourself, but yeah, if you can get the part and screwdrivers for a few quid then you could always see if you could fix up the damaged one and you'll have it as a spare or for 3player games which allow the single joycon play like Mario Kart or Bomberman.

Or sell it to someone else or a 2nd hand shop, places like CEX here in Ireland offer between 30-35e for a pre owned single joycon so you could make some of your money back if you were able to repair it later on.

https://ie.webuy.com/product-detail/?id=045496430580&categoryName=switch-accessories&superCatName=gaming&title=nintendo-switch-joy-con-%28l%29-grey-no-strap