DOH! Why haven't i tought of that. stupid me...
It's pretty much just that and maybe healing an AT gun that you're
really afraid you're going to need soon 'cause those things have to walk all the back to the base med bunker.
The difference with Brit heal is quite large, it heals in a radius (so you can get multiple units healed simultaneously), it requires no cost after the initial investment. It is micro light, a single click gets it done. And it comes on multiple squads making full health healing easy. The only real similarity is that they are both carried by infantry units.
Ambulance heal also always healed in a radius, but microing the (finicky) medics that'd you have bail out of the Ambulance when the latter is cooling down and getting them back in when Ambulance healing is up again was way more dicks than like, getting two medic ISes at most and having to click just one of them.