Don't know them at all but you could get a quote from them and Geotrans. May be worthwhile going to see them and inspect the storage facilities regarding security.
It seems you can rent a van which can be double locked and parked in their outside parking lot bordering a canal (?) for as long as six months for $45 @ month. There is security as this is a ministerial parking lot and a ministerial van..I've visited the premises and inspected the van and received a business card. I'm not packing any Romanov eggs. Has anyone heard anything adverse about this practice?
I honestly do not know anyone who has had to store goods in Vientiane. If the yard has 24/7 security, is a ministerial car park and you have the keys to the van then it may be worthwhile. Cost wise it seems okay.
Might also be worthwhile looking in on the establishment at different times of the day and night and check out the security.
Articles to help you in your °µÍø½ûÇø project in Vientiane