I scooped up the Binbok Joypad Controller to replace the joycons on my Switch (nothing wrong with them):
I chose this over the Hori Split Pad Pro because, unlike the Hori, it's feature complete with the joycons. The Hori is missing bluetooth, so it can only be used in handheld mode, and gyroscope (granted I don't currently have any games that use gyro and possibly never will).
As you can see it's not much bigger than the joycons when used as a separate controller. 95% of the size difference comes from the insert in the middle that links them into a controller, like the shell does for the joycons (and adds grips). I mainly bought it for handheld mode, but it's nice to have the ability to use it apart from the Switch so that I don't have to lug them and the joycons both around to be able to play while docked. I was hoping the shoulder buttons would be spaced a little more apart, but, as you can see, the spacing between the bumper and trigger is basically identical to the joycons.
The face buttons are technically bigger, but only microscopically so. I very much like the analog sticks on the Binbok better than on the joycons, they have a bigger range of travel and stiffer resistance, which I like. I also like the D-Pad better on the Binbok. There's turbo, which I haven't tried yet but may come in useful some day. There's RGB around the sticks, as you can see, which can do rainbow and cycling and whatever. I don't much care, I just set it to whatever color catches my fancy at the moment (currently violet) and leave it at that.
The built-in grips make the Switch much more comfortable to hold in handheld mode. I didn't think the Switch was uncomfortable to hold before, but it's certaily more comfortable with the Binbok.
The one concern I have is how light the Binbok is. It certainly feels flimsier than the joycons. Only time will tell how well the Binbok holds up.