Which would you use and why?

HPS will shit on a LED. True 1000 watt LEDs are mega bucks. Most cheaper LEDs that claim 1000 watts are more like a quarter or even less, in real output. One easily found light on ebay claims their 1000 watt has a real power draw of only 100 watts and is their recommended "equivalent" for a 250 watt HPS.

The HPS will certainly give you the best flowers in the end but the LED might produce less heat if you have trouble controlling your environment. Go forth and be fruitful x

@Drmambo, yea, your 600w HPS is the better choice. I'm 100% sure. If you paid €25, I would be surprised if the true wattage was over 75w. Your HPS will be infinitely better.

Then your 600w Hps will be the better choice.. Your output will be exponentially more.. Leds grow great but in my opinion you wanna run 150-200 watts a plant. different types of leds have different output potentials.. but in order to get a "600w" hps equal yield you need to be pulling at least 300w+ from the wall with the led in my opinion and when Iv'e compared to growers using bulbs... Lots of growers still grow with bulbs because they have setups in excess of 10+ 1000w bulbs and converting that type of light output to leds is very expensive.

@the8thchevron I got the led one for like 25€ online does this sound like one of them

If its a legitimate 1000w LED, definitely use that, they have higher efficacy and have more usable light. Its more likely, however,that your "1000w LED" is really like 150w-250w, in which case use the HPS as long as you can control the heat.