as often happens, the power rating does not match with the actual performance together 4 Watt should be but there are 6 watts and the luminosity is also as 6 watts - well so far but when buying lamps you follow so a specific goal, so if I want to replace 20 watt halogen I need (depending on the quality of the lamp) 3 watts for a little less than 20 W halogen and 4 watts for a little more than 20 watt halogen - now I have the brightness of 35 watts - I want but not really - now it is extremely bright In addition, there may be a wrongly dimensioned transformer when using many lamps Example: I buy a 50W transformer and 10x 4Watt LED - fits now have the LED is not 4 but 6 Watt - and wupp - My transformer switches off due to overload
the format of the lamps is dimensioned slightly too large, I had swelled from heatsink abfeilen around half a mm so that I get the bulbs into the socket when I count the time for rework, then I would have to get money from the seller
Conclusion: The lamps are not bad, have 6W and 35W halogen are replacement for about and I'll keep those things, hopefully they keep at least