I just bought the levelling system

[LM]

The cons for this type of tiling is the fact that it is prone to
leaving voids in your work,up to date no one has published
details to this respect.
also how much time does it add to a job.

Using levelling clips or not, ill prepared substates will lead to voids under tiles if not addressed. The clips are brilliant for the SLIGHTEST of adjustment to clamp adjoining tiles level with each other on properly prepared substrates and in that regard do save time. Yes they cost money and do take time to install, but the difference in time taken to achieve the same quality of flatness in comparison as to when not using them is considerable. Personally I think it speeds up achieving that level of finish. If tiles are back buttered on a correctly prepared substrate then they are an advantage!

 

[One Day]

The cons for this type of tiling is the fact that it is prone to
leaving voids in your work,up to date no one has published
details to this respect.
also how much time does it add to a job.

They CAN make a "tiler" lazy enough to create voids.
In themselves they don't create voids though.

Used correctly they save the time adjusting levels and tweaking, as well as the risk of adhesive slump.
Used poorly - they can make a spot-fix job go really fast and look great. That is the main risk in my opinion.

 

[average]

As I said 600 x600 they have as 11 straps PSQM
600x600 x3 = 1.08
1.08 x11 = 11 .88
I don't know pretty close to 12

Yes that's onecsq MTR but if you put 4 sq meters beside each other, you won't use 48!

 

[Dumbo]

Firstly if you did one square metre . Well actually it would 1.08 sqm you would not use 11 you would use 8 only . But quite correctly you wouldn't use 48 on 4sqm .well actually it would be 4.32 sqm you would use 34 .

 

[LM]

This is getting silly lads, if you lay two tiles you'll use 2 straps, 3 tiles you'll use 4. If you lay a long narrow corridor it will have a different ratio than a large square room. 11 straps per mtr is an average for 600x600, chill out!

 

[Dumbo]

This is getting silly lads, if you lay two tiles you'll use 2 straps, 3 tiles you'll use 4. If you lay a long narrow corridor it will have a different ratio than a large square room. 11 straps per mtr is an average for 600x600, chill out!

I know that and I agree with you totally but apparently that needs to be demonstrated to me by some people