standard downlights now to convert to LED bulbs later on

which is the best fitting to put in?

I get confused by GU10 or MR16 and don't really know the difference.

We don't have the budget to fork out for LED downlights right now, but can gradually change the bulbs over later on (when they become cheaper)

recommendations please

GU10 is the go if you want LED later on.

So my 2c worth - because I am in what seems to be the same boat...

Summary from what I can tell between MR16 and GU10

MR16 - Low voltage, requires a transformer to get the low voltage, most common, brightest and reliable
GU10 - 240 volts direct - no external transformer, easier to install

Now as far as LED updates
LEDs mostly require constant current transformers to operate reliably, the run of the mill transformers for halogens are closer to constant voltage - but are not always even that so you may not get consistent results from these transformers for the MR16 LEDs - look at needing to replace the transformers as well ( hence not plug and play as I had hoped ). It does seem that there are a few LEDs coming on the market that can handle the standard transformers, but there is a cost premium that goes with that.

For the GU10 LEDs, LED's really hate the heat ( much much less than halogens ) and given that they still need the transformer, they just squeeze it into the base of the LED, and with most things that are shrunk down and get hot their life is not likely to be as good as one that does not have this challenge ( the MR16 has the external transformer ). But they are easier to update.

Given the costs as they stand today it is a hard call to go all LEDs if up front money is tight and with no clear path to just swap out the globes ( at a reasonable cost with today’s LED offering ) jumping out at me.

So what to do - as it stands today I am looking at using the 35 watt MR16 IRC Halogens ( these are the lower power use offerings in this range with light output of a standard 50 watt halogen ) and waiting to see what happens on the LED front.

Good luck.

Really confusing to know what to do isn't it!

We are going with the GU10 CF downlights. When we researched it seemed that some transformers were ok with LED bulbs and some weren't - hence why we went the GU10 style, avoided the separate transformers all together.

I think it all depends on who you talk to and what their preference is as everyone seems to think one is a better option than the other.

With a new installation there is a cost benefit in using LED GU10 lamps as opposed to MR16 lamps in that there is no need to purchase the external transformer required for MR16 lamps. Depending on how many lamps you're installing these transformer costs can add quite a bit to the already high cost of LED lights.

I've got existing halogen MR16s I am looking at converting to LED, and have the added complication of not knowing if the LED MR16s will be compatible with my existing transformers!

you guys also have to be careful if you want dimmable LEDs or not as the price is very different between the two.