Storm is hard to drive *well*. You can get it to make a noise from pretty much any device, of course, but it is one of those transducers that scales massively with better sources and amplification. It can defeat a lot of even very good portable gear, and it's only when you hear Storm driven properly that you really start to appreciate it.I want to save up for Storm! But i heard it one of the hardest to drive and i like portable not stationary. So XD05 pro is viable option.
You can combine portable amps to get more from Storm, imho, if you don't want to go for desktop gear. For example, using line out from the XD05 PRO into a dedicated portable amp will likely deliver better results than just using the XD05 PRO alone - MASS-Kobo 475, iBasso PB5, Cayin C9, Analog Squared Paper TUR-08 - would all deliver good results, imho. You can tune the sound quite significantly with different amps. It really depends on budget, preferences, and synergy per the above comments.