Celotex GA3000 and Kingspan T10 / TW55 the difference?

Hi,
Is there any real difference between Celotex Tuff-R GA3000 rigid boards and those by Kingspan such as T10 / TW55?

My local merchants sell the Kingspan range which is much cheaper then any Celotex GA3000 I've seen online. We intend to mechanically fix them to a solid brick wall (internal).

Pars.

The difference between them is about £5

But are they the same kind of product? because the best price I've got is for the Kingspan board at £12 per board (ex VAT / free delivery)

Pars

Given all other physical properties (e.g. foam, mineral wool, etc.) being comparable, the thermal property you should compare is the K value. (measured in W/m.K)

Celotex GA3000 has a K value of 0.023 W/m.K
Kingspan rigid phenolic has a K value of 0.021 W/m.K
Kingspan rigid urethane has a K value of 0.023 W/m.K

So they are all about the same with Kingspan phenolic being fractionally better.

For comparison, the average mineral wool quilt has a K value about 0.040 W/m.K - which is why 200mm mineral wool is about the same thermal value as 100mm foam.