It would be simpler to distinguish the rebranders from the OEMs
In Australia your up for legal action if something goes wrong.
Common guys I know so far you are capable of doing your own comparison searches, I’ll give you the link to the Solen 400v Metallized Polypropylene build specs because I’m not defaming them, but the "boutique" ones you’ll have to search out yourselves.
http://solen.ca/wp-content/uploads/fastcap.pdf Chart regarding length, diameter, lead length ect, is near the bottom of the page. And this is just for the middle of the road Metallized Polypropylene one, there are much more higher and lower spec.
Cheers George