EDIT: Updated based on additional background on catbox and reorganized the file formats

I’ll post some of my experiences so far. It’s important to note that this experience is changing with every upgrade. I use ScreenToGif to convert files, I haven’t used the gif format at all just webm, webp, and mp4:

File formats. For the most part the providers behave the same, I have noticed :

• webp will show an active video thumbnail, and open inline but has no sound
• webm will not show an active video thumbnail, has a smaller file size compared to webp, shows inline, and has no sound
• mp4 will have sound and opens inline, but does not have an active thumbnail (since 18.1)

Providers:

• Direct upload to lemmy
  • uses server resources and probably not preferred
  • some content just errors out on uploading for no apparent reason
• catbox.moe
  • Seems to work ok but the service is sometimes slow or unavailable
  • Has been around for 8 years
• redgifs.com
  • After the 18.1 upgrade, now plays inline but videos don’t show up on the main page
• imgur.com
  • videos don’t show on the main page, but will open inline
  • prohibits nsfw content now, things will eventually get removed as they find that content
• gfycat.com
  • shutting down soon
• youtube.com
  • has the ability to be watched with the NSFW UI patch on here (one of the added expand features [shows on the site as a book] before the update to 18.1)
  • This will probably return soon

Other services I’ve heard about but not tried:

• freeimage.host
• imgbox.com
• imgchest.com
• lensdump.com
• pixhost.to
• postimages.org
• pixelfed

So I’d probably say it’s between catbox and redgifs for me, but since moving here my login doesn’t work for redgifs so I don’t use it any more. I think redgifs blocked my account after I started linking to it from here but it seems like everyone else is fins so YMMV.