http://www.slimliteglass.co.uk/

Compared to normal DG? Does it work as well?

I assume this is slimlite from Edinburgh. If so, the units are intended to provide a DG solution for original/replica Georgian windows with very narrow glazing bars. As such, architectural appearance requires some compromise with thermal performance, and they are inevitably an expensive solution.
There are several window manufacturers who produce high quality replacement georgian style windows which make greater concessions to architectural accuracy utilising cheaper DG, with probably greater thermal efficiency.
My son has ordered a large batch of slimlite for his new-build - I look forward to reporting experience in times to come.

and so how did it go? does anyone have anything further to add on slim-lite?

Almost all sealed unit manufactures can make thin units. We installed some metal frame windows in our new build that were designed for 4-6-4 sealed units. It was easy to find someone to make them. The problem was finding someone to put anything other than Argon in them. To meet the Building Regs U-Values we needed Krypton. Again almost all the maufacturers would put Krypton in them if we insisted but at a significant price premium. The problem is that a cylinder of Krypton is quite expensive and if they don't see any other demand for it they want to charge the whole cost to your job. The trick is to ring round and find a sealed unit manufacturer that already has a cylinder left over from another job. They may have to order the thin seals specially but that's no big deal.

The other thing to beware is the sight line if the bead is smaller.

Wheres the mystery? You can order DG units in any format in 2mm increments from 6mm spacer bar upwards from almost ny dg unit supplier.

You can choose your glass 3mm, 4mm, 6mm, laminated toughened, K, soft coat whatever.
Argon fill....or not.

Ours have been in three years but sadly I can't remember who we used to make the sealed units in the end. Try asking..
http://www.greenbuildingstore.co.uk

Edit: As I understand it the main cause of seal failure is poor installation practice. For example the use of tapered spacers to center the unit in the frame causes the weight of the unit to be carried on one pane. Inadequate drainage can cause water to pool around the seal which then freezes etc.

Posted By: hotelRefurberCWatters, are yours in conservation area windows?

We have four windows from the heritage range here..
http://www.bronzecasements.com/

We had to use the heritage range rather than the better "Advanced System" as they can't bend the profile for that.

Posted By: hotelRefurbergreat looking window! You have an air brick there too

It's actually a periscope vent for ventilating the void under the floor.

See how they work with time then. When I first heard about them I was very enthusiastic, working in the conservation sector, but the company failed to respond to requests for information on how they would comply with the new Part L Regs, and I started to hear bad stories about early failures from guys who had also put their faith in them, and these were construction professionals who've been in the business for a long time. A shame because the concept was a good one, just suspect in practice.