I have my fluids twice weekly, 1 litre over 4 hours. It has improved my symptoms so much I really cannot believe it.
I find faster infusions just give me a really bad headache. Dizziness is almost gone, postural sweating, nausea and breathlessness have all but disappeared. BP is now normal (120/60 or thereabouts), where it was 75/45 previously or lower.
Joining the gym next, which is an achievement considering I struggled with a flight of stairs 2 months ago.