just found out about this new interesting 1xAA headlamp:
EDIT: 96mm lenght… quite a lot (same as Xtar H1 which is 97mm, see images below) looks like the revised version of Niteye JA10
btw… i’ll use this as an archive for future reference 
1xAA/1x14500 HEADLAMPS:
- Jetbeam H10A *NEW* JETBeam H10A & H10C Headlamps | Candle Power Flashlight Forum
- Fenix HL50 (AA or CR123A but no 14500/16340 unfortunately) http://www.candlepowerforums.com/vb/showthread.php?387489-Fenix-HL50-(XM-L2-T6-Neutral-White-CR123A-or-1xAA)-Review
- Xtar H1 XTAR H1 Commander Headlight (1x 14500 or 1x AA) Review | Candle Power Flashlight Forum
- Spark SG5 (pure flood, but a reflector is optionally available) Review of Spark SG3 and Spark SG5 Headlamp and clip EDC lights. (14500/AA/16340/CR123)
- Niteye JA10 (same format but comes without the head strap though - similar to Jetbeam H10A… same company) Review Niteye JA 10 | Taschenlampen Forum
- and of course Zebralight H52 (H502 is pure flood) and Armytek Tiara A1 which probably set the standard in this category
and a couple of images for size reference (too bad the H1 is so long…)
in the middle: Xtar H1, Fenix HL50 (AA setup), Fenix HL50 (16340 setup)
in the middle: Zebralight H600, Xtar H1, Xtar H2
from left: Fenix HL50, Spark SG5
Fenix HL50, Zebralight H52, Armytek Tiara A1
P.S.
i personally prefer 1xaa/14500 headlamps to 1xcr123a/16340 because when you are using rechargable lithiums you get better performances with 14500 size (see here http://www.candlepowerforums.com/vb/showthread.php?345370-AW-16340-750mAH-vs-AW-14500-750mAH ) and should you run out of batteries AAs primaries are way easier to find everywhere compared to cr123a. Not to mention you also have the eneloop option.
On the other hand, the form factor of 16340 headlamps is maybe preferable cause they are more compact (AA headlamps can be quite long, nearly as much as 18650 headlamps sometimes… see Xtar H1 and Zebralight H600)