Well, I used to be the owner of 14 original prototypes, including Death Bringer (x2 copies), Fighter Alpha (unreleased), Sonic 9/20 and 5/10, Detonator Orgun, Mega Schwarzchild (x2 copies), Dynamic Country Club Golf, Cyborg 009, and many others, but in a fit of financial problems I had to sell all but my second copies of Death Bringer and Mega Schwarzchild, which are the only two I have left. And yes, they are originals as well. The real deal.
Oh, yeah, I also had a Captain Tsubasa prototype - that one I sold to some guy in the Middle East (can you believe it?) for $250. He was a strange guy to deal with, kind of like ISO beggers. Every day (even before I got his money) he was asking if I'd sent it out yet. Well, I finally got a bank wire to my account and sent it out 5 minutes later JUST TO SHUT HIM UP!
What's even more sad is that I had the option to a lot of other prototypes through a guy who worked at Sega that quit and was selling them off on eBay. He had something like 28-30 of them, and after I had been the winner on almost all the ones he put up (about 5-6 of 'em), we made an arrangement where I'd send him cash when I could, and eventually buy all of the prototypes one-by-one. I made it to 14 prototypes when I had to cut off the arrangement and I actually ended up selling off most of what I struggled to buy. I'm sorry, but this was like 1999, so I'd have no clue where to find him anymore. Don't ask. Believe me, -I- would love to find him.
However, I did copy most of the others I sold off through a CD-duplication machine (no, not a burner) I had at work at the time, so technically while I no longer have the originals of the other ones, I still have each and every one of those prototypes (minus Alpha Fighter and maybe 1 or 2 others). Thank God for that CD-duplicator, or I would never have been able to save any of them.
Anyhow, I'm in the middle of a move (gotta move by the end of the month!) and I've already packed the Sega/Mega CDs away. When I unpack, I might just go ahead and release my copies to the public domain. Most seem pretty complete, and a couple I can't even play due to the amount of Japanese, but they're all interesting to go through.
I'm just glad you all have that Sonic Beta running around - I wanted to release it a long time ago and I knew of one other person who actually owned a copy. I'm glad he released it, because at the time I'd have not had a clue how to do so.
As you can probably tell, I'm almost excusively a MegaCD collector. I have an original Japanese Mega Drive and MegaCD2 system, and about 15 original MegaCD games, along with those 2 prototypes. I've also got a Genesis and SegaCD2, and a Japanese MegaJet portable system in the box, brand new. I'm glad there's others like me around, who thought the Sega/MegaCD wasn't as bad as everyone thought. Keep it up!