I realised that I already had some similiar as yet unused Forstner bits but only up to a diameter of 40mm, so I took them for a test drive.
The results are sobering.
On the first picture you can see the results of drilling without a drill press.
The holes marked 7 and 6 were my first attempts with a 40mm bit. I put a lot of weight behind them but was unable to control this at slow speeds.
Holes 1 and 2 were made using the 20mm bit. the quality is still pretty gruesome.
Holes 3, 4 and 5 were made with a 20mm Fisch “Wave Cutter” Forstner bit. On 4 I slipped slightly but the other two look pretty good.
So I will not be ordering the 95mm version as I do not expect any decent results even with a drill press.
The quality of the bits themselves is also very questionable. The shafts not only vary in diameter by almost 0,75 mm, but they appear to be made of a very soft metal. If you look at the other pictures you can see how damaged the shafts are after only a couple of holes. The final picture shows an unused bit from the same series for comparison.