CF to IDE should be relatively problem free as long as you choose a good CF card. CF uses the IDE interface so it the CF-> IDE converters are only passive converters.

A good 4-8gb CF industrial card would be best, with multiple 2gb partitions.

For Dos/Win3x machines I like CF Cards. SD cards add a level of complexity (as they aren't native IDE) but doubt this matters in real life.
I'd look for an adapter that has a jumper to allow Master/Slave selection that seems to be a good indicator of quality ones.

I don't know of any front mounted options. You can get ones that mount on a I/O card bracket on the back or some people have put the adapter in a standard IDE HDD caddy.

You cant hotswap. You would need to turn the PC off each time removing the card. What you can do however is have 2 of the same cards and switch between them from different setups.
BIOS sees the same HDD with same geometry when powered up, it doesn't care about the contents.

Indeed DOS 6.22 is limited to 2GB but that's plenty for a dos/3x install, you can then create more 2GB partitions for games, data, etc
If you want to break the 2GB limit you can use the dos that comes with Win9x aka Dos7. This'll give you FAT32 and you can still install Win3x with a slight tweak.
You also have a few alternatives to MS Dos like PC Dos that also support Fat32 but Haven't played with these myself.

chinny22 wrote on 2021-05-05, 09:35:

I don't know of any front mounted options. You can get ones that mount on a I/O card bracket on the back or some people have put the adapter in a standard IDE HDD caddy.

You could make one yourself easy enough, but, Startech do sell one:

I use them in all of my older systems - it's far more convenient that the rear panel mount. Just give the metal frame a quick respray in your chosen colour (I've looked - there used to be a beige version years ago, but the only part now stocked/sold is the black one linked above).

I second the Startech adapter, well built and absolutely zero issues. It's guaranteed to work, whatever the age of the mainboard it's connected to.

megatron-uk wrote on 2021-05-05, 10:53:

You could make one yourself easy enough, but, Startech do sell one:

That's a pretty nice looking adapter and it supports 3.3V which can be a plus if you run into the rare CF device that requires that, like the "Extreme CF Adapter" for SD cards.

Why does it have the second PATA 40 block connector? Slave devices?

p.s. I used this-- https://www.tinkercad.com/things/gssA8iCuv6M-35-bay-cf