Omega uses Renata as has already been stated. However among watchmakers, Renata has a bad reputation for leaking prematurely.
I personally do not use them for this reason, and I use Maxell. Now I don't service a ton of quartz watches, and since I am not in a retail location, I don't do battery swaps by the hundreds each week (thankfully!), so the recommendation of Maxell came from another watchmaker who primarily works on quartz and does trade work, so he swaps a lot of batteries. He's the kind of guy who keeps the old batteries and sells them by the kilo for scrap - they contain silver...it would probably take me a 10 years to get a kilo of used batteries....and he sells this much every couple of months for scrap.
I have never had a battery that I installed leak, so to date I am confident in the Maxell.
$300 does seem cheap for a service or replacement of the movement. The movement alone is $250, so if they are swapping it (most likely scenario) then they are not charging much for the remainder of the work. It could be that they are actually servicing the movement, but usually corrosion damage is something that requires at least the circuit to be replaced.
Anyway, good luck with the watch.
Cheers, Al
Click to expand...