Quote Hi everyone, been a long time user of pd but lately it just seems to be laggy and slow, im running a dell xp15 laptop so not a slow machine by any means i7 16gb ram ssd

Mate that is a slow machine. Especially if you are editing 4K content. Firstly it is a laptop, secondly it is a Dell that is known for quality control over heating issues. Moreover, a laptop i7 isn't anywhere as good as a desktop i7. But I do feel your pain.

Now the helpful bit -

PD is good for just cuts and trims but as soon as you do any sort of color grading, LUTs, effects and try to preview, everything gets choppy. This will even be more noticeable because you have a laptop.

I'm assuming you are using "Shadow files" options, if not use it which might improve your results.
Identify the clips/areas in your timeline where you have complex effects/heavy grading etc, and use "render preview" option.

Unlike Premiere pro where as soon as you put "warp stabilizer" on a clip, it takes a few minutes for it to "apply" but PD you apply stabilizer, unless you preview it, it is not applied until you render. So, it might help if you "render preview" for the complex areas of timeline and then keep editing.

but during preview paybac ad edits of clips that are sped up past 10x will be all laggy making cutting to music guesswork, colour editing clips is also not doable

PD provides basic color grading as well as LUT support.
If you need more color grading, there is Color Director you can which is still much cheaper than Premiere pro.

as the finished product looks rubbish with artifacts and banding everywhere after its produced,

Artefacts and banding is not acceptable no matter what.

this is on 4k hq footage,

What is "hq" ?

coupled with the constant spam to upgrade that and photodirector all the time i'm wondering if its time to switch to something a bit better that may run a bit better?

Probably is time to switch if you like premiere pro better and can afford it.

Thanks for the reply -

HQ, high quality i.e. high bitrate.

The spec of the laptop is -

15.6" - Core i7 7700HQ - 16 GB RAM - 512 GB SSD - English

I'm going to double the ram and see if that improves things.

I use shadow files already in editing

Quote Thanks for the reply -

HQ, high quality i.e. high bitrate.

The spec of the laptop is -

15.6" - Core i7 7700HQ - 16 GB RAM - 512 GB SSD - English

I'm going to double the ram and see if that improves things.

I use shadow files already in editing

RAM may or may not improve your performance. Good way to check is once you started editing/rendering, open up task manager and you'll see that the CPU will be 100% but RAM will be like 30 or 40 or 50%. This suggests that RAM upgrade may not be necessary. What we both need is a better CPU (preferably desktop but I cannot have a desktop because I move for work a lot)

Either we both need better CPUs, OR, Cyberlink Powerdirector to work as smooth as FCPX works on Apple OS via software optimization as software-hardware optimization can go a long way.

I have the same set up but in a Gigabyte laptop. I also have GTX1060 card which helps.
If you also have a nvidia card, try this -

https://forum.cyberlink.com/forum/posts/list/64906.page

Thanks i have nvidia gt1050 so have done the steps you linked to to try it