When I started making this back in 2003 I figured that I was the first person to construct a fully functional 3x3x5. However I discovered that Katsuhiko Okamoto was also making one and later I discovered that Aleh Hladzilin had made one previously, though both used different methods to mine.
The puzzle was transformed entirely by hand using high impact polystyrene plastic sheet. As stated my puzzle is fully functional. That means all rows and columns can be independently rotated.
I am very pleased with the quality and I would rate it as one of my best puzzles. Rotational movement is very smooth. I have used standard Rubik's Cube style stickers with blue opposite green, red opposite orange and white opposite yellow.
When other people make this puzzle they usually (always?) do so by adding extra layers to regular 3x3x3 Rubik's Cube. This means they need to add new functionality. There's nothing wrong with that but making new mechanisms is always tricky and has to be done in an accurate and precise way. For that reason I chose to make mine from an Eastsheen 5x5x5. It's a little bigger but I did not need to interfere with any mechanisms. It's just a basic cut-down and build-up transformation.
The puzzle can change shape since it obeys the rule- "A cuboid is capable of shape changing when ( two or more edge unit lengths are different and odd ) or ( two or more edge unit lengths are different and even ) excluding cuboids with a side of one".
In total I have made twelve fully functional cuboids. They are-
2x2x3 (micro), 2x2x4, 2x2x6, 2x2x7, 2x3x4, 3x3x4 (large), 3x3x4 (medium), 3x3x5, 3x4x4, 4x4x5, 4x4x6, 5x5x6.
Factory made 3x3x5s are available below. They are not proportional though.