This page contains a review (of sorts) and analysis of Travel Zombicide, a miniature version of Zombicide 2nd Edition. We'll abbreviate it as TZ from here on out. This article is not a review of the underlying game (Zombicide 2E), but only of the aspects of TZ which make it different from 2E. i.e. only aspects pertaining to its minuscule size.
Pics or it didn't happen, of course: the ongoing TZ photo album (yes, i painted them!)
We'll start with the summary. In short, TZ is too small to be easily playable. A good deal of the play time is spent fidgeting with pieces or trying to shoe-horn another zombie in to a space which cannot hold it. TZ was a nice idea and well worth a try, but its greatest assest - its size - is also its greatest weakness. i don't regret buying it but cannot recommend that anyone else do so.
To keep this simple and straightforward, the following paragraphs are bullet points of what stands out about the game (both positive and negative) compared to its larger cousins.
Mini does not mean trimmed-down. One of TZ's strongest attributes is that it's small without being trimmed down. With the exception of having only a single Abomination, compared to 2E's four, and six Survivors instead of 2E's 12 (lacking kid Survivors), it is every bit as functionally complete as the 2E core set. (For whatever reason, the creators chose to use the mini sculpts from 1E instead of 2E. That's neither plus nor a minus, just a bit of trivia.)
It really does all fit back in the box. The design of the case/board combination is rather clever, IMO. Everthing in the game fits comfortably (back) into it, without requiring that someone push down on the top while someone else fastens the latch. There's even a bit of extra space which can be used for storing extra dice and such.
A complete unboxing on every use. In order to play TZ, the players have to remove literally every piece from the box, even those they won't use, because the box is the board. This is not only fidgety, but (ironically) also takes up more table space than the game actually needs.
Cards are too small to shuffle. The cards are about half the size of US-mini (the prevalent size in both 1E and 2E), making them impossible to riffle shuffle and impossible to sleeve. The latter means, by extension, that they're impossible to "mash shuffle." Randomizing the spawn and equipment cards is a huge pain in the butt.
Minis/map size mismatch. TZ has the same zombie minis count as 2E except for the abominations: 73 tiny minis. In 2E the designers increased, on average, the number of zombies spawned by each card. That, however, is fundamentally incompatible with TZ's form factor: it's easily possible to spawn more zombies at a time than will fit in the space they're spawning on. The physical per-zone limit on minis is somewhere around 8-10, or closer to 6 on half-zones along the edges and 4-5 in some indoor spaces. (Due to one particular mission's special rules, in which 3 spawn tokens can be in a single half-sized zone, it's possible to be spawning 15+ minis each turn in a space appropriate for holding a 3rd of that.) Because of this, players will eventually have to resort to bookkeeping techniques to track how many zombies are in a given space. e.g. adding small dice or tokens. There's an inherent mismatch here: if the minis were any smaller than their approximate 12mm height, they would be nearly impossible to manipulate. If the map tiles were any larger than their 81mm, the game would lose much of its size/space advantage over the full-sized game. The tiles, however, really need to be 12-15cm across to be usable (contrasted with the full game's 25cm). That, however, would probably eliminate or complicate the design of TZ's current box/board combo.
Card clip disrupts play. Each character sheet comes with a number of clips with which to track Adrenaline (AP), skills, wounds, and a much larger one to clip the character's equipment cards to the character sheet. The latter literally gets in the way of the AP tracker: moving cards into and out of the card clip often causes them to nudge the AP tracker's clip, moving it around or knocking it off. That clip makes the cards "travel proof," in that they'll stick with the character through the bumps and curves of automobile travel, but it otherwise just gets in the way.
Unstable playing surface. It's no surprise that the tiny minis fall over at the slightest provocation. The game surface is plenty stable when it's on a table in a non-mobile house outside of California, provided nobody nudges it (but see below), but is unsuitable for any remotely jittery enviroment, e.g. a table in an R.V. or van, or anywhere in California.
Dice mounted on the board lead to board nudging. The six dice spinners mounted along two edges of the board work surprisingly well, but it's easy to inadvertently nudge the board when flicking them, causing minis to fall down, potentially into a space other than the one they were standing in. Chaos ensues.
That's all that comes to mind, given my limited experience with using TZ.