I recommend the DTX50 BUT change the ear tips if the stock ones aren't any good. With the stock tips I was initially disappointed with the DTX50, but now I use the CrossRoads Bijou double flange tips, which I had lying around and they are a perfect fit! The beyers sound great now. They really can sound good with the right tips.
Maybe the amp makes a difference. Many have said that the DTX50 sound muddy, but mine didn't. I use a Go Vibe Petite. Perhaps the Petite brings out the highs.
I can't imagine how the custom moulds sound, as they are only available in Germany. But must be a good bang for the buck.
I bought the DTX50 for $74 and I use them maybe 70% of the time. I use the Sleek Audio SA6 for the rest of the time for portable use. Strange really, as I am a big fan of the Sleeks. Great timber, great sound, but the DTX50 highs and lows are toe tapping at times, while the Sleeks don't always reach out and grab my attention.
Many will disagree with me, and fair enough. But my advice is to listen to what headphones you can, then decide.