The first thing I noted when looking at the link was
LED bulbs require a constant current to work properly.
yet it seems to be showing a constant voltage supply, second is
This LED Driver is the perfect product to replace the 12v transformer which is powering your existing low voltage MR16 or MR11 downlight, and your G4 fitting
but it has a DC output and most the MR16 I have looked at are marked 50/60 Hz so are AC units.
I am sure many MR16 lamps will work with a DC supply, but I expect some which say 50/60 Hz actually do need an AC supply?
As the constant current main advantage is it auto compensates for volt drop, so one can install a line of lights down the side of a 2 mile runway and every lamp is the same brightness. In real terms the transformers are wired in series so losing one bulb will not cause all the lights to go out. In domestic I can see the advantage when running down a long garden, but 75 volt is maximum for extra low voltage DC and 3 volt approx for a white LED, so 25 LED's is maximum in real terms more like 15 LED's keeping under 50 volts as often not ripple free.
What I see as a problem is a fitting which can take a lamp anywhere between 1 and 50 watt AC or DC with nothing at the lamp to say what should be fitted. Add to that angles 15° to 36° and often under the care of just an instructed person. Unless we use the LII GU10 where a dimple is required in the lamp for it to fit in the holder we have no way to ensure an LED lamp is replaced with an LED lamp.
Some power supplies will auto shut down with over load, likely the linked ones will, but there is nothing in the spec that says it will auto shut down, so either you need to fit fuses or get one which says it will auto shut down.
To my mind it's a watch my back exercise, if the unit says it auto shuts down on over temperature and over current then if some daft twit fits a 35W quartz bulb then if it goes wrong it's not your fault. Be it needing a class II sticker or having a stated overload device as electricians we have to ensure they are fitted. As a DIY guy you can take a chance, if it does go wrong your unlikely to be taken to court, and if DIY in your own house you are unlikely to try fitting a spare 35W quartz as you know transformer only rated 25W, but as an electrician you have to expect at some time some one will say, I'll just borrow a bulb out of this table lamp until I can get a replacement.