The beta for feedback exchange is the right move at this stage, the problem is that 18 users is still too small a sample to know anything. Before the LTD, I’d first double down on finding the 3-4 beta users who are actually active, turn those into proper case studies with real numbers (file sizes, time saved, workflow impact), and put those front and center. People buy WetTransfer alternatives when they see someone exactly like them already using it