First of all it is important to know which is installed transformer for the power supply of the halogen or LED's.
Old transformers often need a certain number of watts to work only. It is therefore important that the same transformer to exchange with. Here at you should also pay attention to how many watts the transformers are designed.
Within the selected LED's here:
For the price of prime, this was the best choice in Amazon here. The order was delivered the next day and the conversion could be started directly at the weekend.
To mount the LED's, as they are larger than conventional halogen G4, it may be that they do not fit in each housing, thus leading to problems. With us, the Assembly has gone reasonably well, called the cap had to be closed by pressure. Here are important dimensions of the G4: "32mm long and about 9mm diameter". The diameter is not the problem the special length is specified here with 36mm. You can shorten the pins something more can not be done.
To light:
If you do not look directly into the cone can be seen in the room is almost no difference to the halogen. If you look directly into the reflector the light shines somewhat brighter than a halogen, but if one is looking at the space subjectively noticing no difference. The LED's are to be compared with 10-15Watt halogen bulbs of the luminosity. The 20 Watt bulbs that we had before are a bit more noticeable. Illumination is good, because the LEDs are arranged in a circle and therefore a good illumination is guaranteed.
Save yes or no?
We have for now 3 LEDs to replace the 20 watt bulbs that makes about a savings in excess of 55 watts. In relation to the 20 watt halogen are somewhat weaker, but they are out of proportion to the savings of approximately 90%.
In the future, I can well imagine that LED bulbs come on the market, send the halogen immediately into hibernation. For the uplight there is still no acceptable comparison, since the LEDs offered creating just 1,000 lumens, the halogen which swallow up to 500Watt create an illumination of more than 3500 lumens, and more.
For the exterior, there are already comparable floodlights that are offered but still very expensive!
Nevertheless, I would give this product a full assessment, even if they are not 100% comparable to halogen, good enough for me saved to make more than 90% to a compromise.