Theremin

A friend and I are looking to build a Theremin as a project. We've scoured the internet for schematics and have found some good ones. We are left with a question whether to use vacuum tubes or transistors. We've discussed the durability and cost differences between the two, but we're curious as to how much different the two sound. All that I've been able to gather is that tubes sound vaguely "better." Does any one have any experience between the sound of tubes v. transistors? Thanks in advance. Zach