£185 is a lot of money to 'test' whether you like night riding, as it simply isn't for some ppl... no idea why not, but it's not.
That said, if you are determined you will do it & want a solution that 'just works' & backup that is tested in the real work , then you can't go wrong with MTB batteries units.
Unlike previous years, this years 'recommended cheap chinese light' has really quite bad ancillary kit that come with it (battery & charger), not to suggest that previous years were perfect, just not quite as bad. That said, if you buy the kit from a UK supplier and it turns out to be rubbish... send it back!
So without trying to inundate you can I suggest you look at UK seller like these guys (I'm not connected to the business nor have used them)