Dypsis pilulifera (aka orange Crush) is not really any harder or easier to grow than most of the large Dypsis. In Hawaii, it is a very fast growing palm. In a Mediterranean climate it is slow, but certainly not one of the slowest.

From a one year old seedling. About just 3 inches tall or so , after 8 years in med climate, what size would it be?
Does this palm like plenty of water? Or can it handle drought?

Most Dypsis need a lot of water until they are larger. I don't know if this one can handle drought as no one has one large enough in a drought area to test it yet.. but I would recommend it get watered regularly (as all Dypsis should with a few exceptions... like triangle palms are definitely drought tolerant, as are mature Dypsis decipiens). 8 years in your Med climate it might be starting to think about trunking, but could take another 2-3 years. In Hawaii, it would have a trunk already.

Are these palms easy to get?

often available from Floribunda Palms and Exotics (Hawaii) and they send all over the world

Must contact them. Guess then these palms should be happy in Madeira. Sub Tropical with plenty of rain is just the job.
Would buy a larger specimen about 3 Gal, should be stronger at this stage. The orange trunk is a real talking point.

They say as seedlings, these seem to be on a death wish . At what age are they more stronger? I have a small seedling, 2 inches tall, about 6 small leafs. Just over year old. It's new home will be in Aruba, Carribean. I am hoping there it will speed up. I will set up water system. Keep in shade until trunk forming, then put in ideal position in yard. What attracted me to this palm was it's orange trunk. I know it grows tall, so will choose correct position for it. ( although slowth growth means I will never see it tall) something for my children to injoy.