MR16 kitchen downlights 50w / 35w

[Mobius1]

Having rented my flat for over 3 years now, one of the 4 low voltage downlights in the kitchen went the other day. I hate replacing them because of the stupid pinch retaining rings.

I went shopping today and picked up a pack of 3 Philips MR16 50W halogen lamps. Went to take the old one out and, on inspection of the old lamp it's 35W. There's nothing on the fitting itself that denotes a maximum wattage and in terms of uniformity I can't tell the different between the one I've replaced and the others.

I'm wondering if it's safe? They're all obviously connected to a transformer somewhere. Not knowing the rating of it though there's no way for me to tell what it is. It's a bit shameful because I used to work in an electrical wholesalers and sell tonnes of these but I've totally forgotten. Yay or nay?

[mjwman]

The transformer will not last long if you use the 50w lamps.