My cages arrived yesterday - they're not on the bike yet due to a lack of suitable fixings, but below are some pics and initial thoughts for what they're worth
Upon arrival I was concerned by the mass of the box that one cage had been sent. I was reassured to find two inside; which felt very light once in the hand. The published mass is 48g per cage however these both came in at between 42 and 43 grams each on my scales. For reference I think the Zefal CFRP items on my road bike are about 28g; so while certainly heavier the weight penalty compared to other cages is hardly significant.
I was disappointed to find the cages a somewhat on the wonk to varying degrees; I've managed to bend them back a little but they're still not dead straight. I had a similar problem with some Topeak ally items I bought previously for this bike and they went back for a refund as the wonk was worse and there was no chance of correcting it as the welding was partially to blame.
I elected not to return these since it looked like it could be corrected to an extent (I suspect I might have to tweak them to fit the bottles better in any case, as they're potentially a bit tighter than I'd like) and I've pretty much run out of alternatives in any case...
Wonkyness aside the cages generally look like nice quality; with a fairly consistant semi-matt / brushed finish on the tubing. I was impressed by the quality of welding too; which is very intricate, clean and precise at both the joint in the tubing and interface with the mounting sections:
So there we go. For now I'm certainly not regretting their purchase and am looking forward to getting them on the bike once I've sourced some appropriate fixings.
Finally I'd like to mention
Bikemonger - the supplier from whence these came. They seem like a nice, small outfit, the price was good and the transaction all went through as it should. I got a nice personalised message on the receipt and the guy who runs it seems like a thoroughly decent chap; so I'll be keeping an eye on them for anything else I might need in future