As you are on Mac you can use what people were using before HAP which was mostly ProRes. Youve also got the option of image sequences.
Transcode speed, you will find encoding to FlexRes Quality will give you great quality and be double as fast encoding than it is to encode to FlexRes performance. Of course FlexRes Quality will look great however you can play less layers with FlexRes Quality than FlexRes Performance.
If you were using windows I would reccommend downloading our FlexRes Tools so you can encode straight to FlexRes with out using an intermediary codec.
This is a real issue out in the field dealing with content creators using the Mac platform (amazingly there's more than a few of them). With the los of HAP, the transcode time on anything coming out of OSX land has just killed content ingestion times and really become a hassle when dealing with large quantities of media.
Unfortunately at this time, there are no cross platforms Codecs that are suitable for media servers. FlexRes is our own in-house codec, but is only for Windows. For that reason we encode everything into that. HAP was a suitable cross-platform codec for media servers so we didn't have the requirement to encode them again. With the pulling of support of HAP, there is now a gap in the market for a suitable cross platform codec. Until one appears the status quo will unfortunately be that the content will have to be re-encoded.