I used to have Optimate 3s on all my bikes but one died unexpectedly and I couldn't bring it back to life.
Before I got round to buying one I picked up a cheap one from Aldi to give that a try.
https://www.aldi.co.uk/auto-xs-car-b...90030347442700 It's lived on this for over a year now and I've never had an issue with it.
I think that charger technology is pretty much common place these days, compared to say 20 years ago when it was only big name brands, so just about any charger will do the job.
I always cut the ends off and fit optimate connectors
