I prefer the TCT countersinks as they drill a decent sized clearance hole in the top piece of wood and either countersink or if you go a bit deeper a counterbore for plugging. I use the 4mm, 5mm & 6mm ones but the 4mm gets the most use. Also being TCT they don't get blunted easily when used in MFC & MDF. Also take easily obtained standard metric size drill bits.
I have been using this type of bit for ages and have used many different versions, I will do a quick list.
Dewalt flip drive bit. Very strong and robust, reasonable quality, quite expensive (£25 + ) . Be aware that this one is very much larger (in diameter ) than the trend ones. I found this annoying when trying to go near corners or through small gaps.
Trend Snappy flip over bits. Very good overall, good quality, quite cheap (under £20) . The trend ones are quite slim which is good, they have a sort of `double` countersink with a short thin countersink before the main one. Also you can have a problem with the drill bits getting stuck. When the small drill breaks off (which they will) flush with the end of the countersink it is virtually impossible to get the remaining piece out and thus a new one in.
Cheaper copies unbranded. Ok if you only need them a few times but not good quality.
Makita Quad drivers. Makita make 2 versions of these the first is the cheaper (£15 ish) Black sleeve one which is pretty much the same as the Trend ones in size and design (barring the `double countersink` ) These are good but suffer the same problem as the Trend.
The second Makita ones are called Professional Quad drivers (£25 ish). Silver sleeve. These ones are the best of all I have tried. They are slightly larger than the Trend and black sleeve Makita, but still much smaller than the DeWalt. The advantage these have is first that they have a grub screw to hold the screwdriver bit in tight, and second is that the screwdriver bit holder and the drill bit holder can be separated with another grub screw which enables you to remove broken drill bits easily. replacement Makita drills have a flat on, so I always get the official ones. They are the best quality I have found. Also they have a handy allen key bit attached to the shank so you don`t need to find an allen key.
I only use the Makita Pro ones now.
These are available in many different sets so it depends if you need the three sizes or just one size.