First-timer here, please be gentle...

I have approx 8 sq m floor tiled - toilet/bathroom - 18mm wbp ply screwed on to joists, 300mm centres, noggin'ed @ 300mm. Ply was primed using 2 coats BAL prime APD, Schulter-DITRA membrane set over ply using BAL fastflex, and 25mm mosaic in one-foot sheets set over membrane using same adhesive. (This floor construction is necessary because of the warm-water underfloor heating pipes under the plywood)

Now to grout - Topps Tiles offered me Microflex. Is Microflex, Microcolour or Easyepoxy best to use? Or perhaps another brand? I've read elsewhere about some of the inconsistencies in Bal grouts when they've dried - I'm after a flexible grout like Microflex, with good water repellency, and would appreciate some advice.

cheers

Mapei Ultracolor Plus is a fast setting and drying, polymer modified, flexible, mould & water-repellent, anti-efflorescence grout. 2-20mm.

Where to use:
To grout joints between all types of ceramic tiles, natural stone, marble, granite, glass, glass mosaic, quarry and porcelain.

Suitable for heavy duty areas, wet areas including power showers, timber substrates and underfloor heating.

Suitable for internal and external use. Can be used on walls and floors.

1 unit = 5Kg bag

Technical Details
-----------------
Pot life: 20-25 minutes
Waiting time before finishing: 15-30 mins
Set to light foot traffic: approx. 3 hours
Ready to use: after 24 hours (48 hours for basins and swimming pools)
Colour: 26
Application: Platinum Grout Float (can be found in the tiling tools section)
Storage: 24 months
Consumption: Dependent on the size of the joint

how are the mosaics on the ditra,are they even?

Mapei ultra colour plus..comes in 26 colours and has water drop effect and anti bio block.

the substrate was originally 5/8" straight-cut joists, ripped out & replaced with t&g wbp board, packed out to level.
Laid ditra on thin bed using same notched trowel as for mosaic, it went on flat, i used a ply offcut to gently persuade it flat.
Mosaics are level - i used a grout float to set, then same 18x12" offcut of ply just to make sure.

i presume u mean level? yes

If you are after any grout other than Bal you can always add the addicitives to make the grout flexible... just a thought

thanks all, used Mapei Ultracolor +, went on well, went off faster than expected so used in smaller batches but easy to clean off excess & polish - looks good