Ok, I here is a copy of the exact email I sent to KR155E...
First pics (top view).


From this veiw, they both appear to be quite the same aside from the labels.
Second pics (label close-ups).


The dimensions of the stickers on each case are different. Each case has a slight indentation on the top that is specific to its sticker/label size.
Third pics (corner shot to show border detail).


Here, we see another slight difference. It may be hard to tell from the photos, but the "border" on the Block Buster case (top) is slightly raised. Whereas the border on the Travel Master case is actually indented.
Fourth pics (Inside shot of the top).


Notice that the Block Buster case (top) has a section of the foam cut out so that an abbreviated set of instructions could be placed there. The Travel Master case does not have this. Other than that, they are identical. This almost makes me wonder if the Travel Master one was either going to be produced for the common consumer, or perhaps it was a proto type of sorts to show Block Buster how the case would look. I have searched all over the internet and can't find any info on the company that produced this case. My guess is that they maybe changed names, or they no longer exist.
Fifth pics (inside the case).


Here is the inside portion of the bottom. Again, the top photo is of the Block Buster case. The only difference here is the small sections of foam on the Block Buster case that show wear. (I took my VB out to take the pics). Other than that small detail, they are perfectly identical.
Sixth and final set of pics (to show similar markings).


The above pictures are what lead me to believe that these two "different" cases were made by the same company. Now, anyone with enough common sense knows that most plastic products are created by using molds. That being said, if a mold has a slight blemish or marking in it, it will show up in every copy of the product that is made. If two different companies are producing the same product, then they are clearly using their own molds. Two molds form two different companies are not going to be exactly the same.
Both cases share many very similar markings. I could take more pics of other such markings, but why waste my time? :-P All this leads up to my conclusion that both cases were made at the same place, and by the same molds. Again, the top pic is of the Block Buster case.
How many cases were made that say Travel Master? I have no clue. Was the Tavel Master case meant to be purchased by consumers that wanted a case more sturdy than the soft Performance case? The answer evades me. Was this just a sort of "sample" case to show Block Buster what they could produce for their rental units? Your guess is as good as mine. If anyone has answers (especially ones they can back up), do tell!
Note: Sorry some of the pics are different sized. I uploaded them to my Photo Bucket account and it must have resized them a little funny.