Disclaimer: I received this product for free/as partial compensation for voluntary help.
This is a 'The Origin' kit, where the models are all based on the 6 (each an hour long) episode show that ran from 2015-2018. It was a prequel to the original show from the late 70's.
The mobile suits have been redesigned to some degree and feature stronger colors, more details and somewhat different equipment which better reflect what humans would have in the future, rather than what was imagined in the 70's.
This particular model is what the RX-78-2 looked like in the early to mid stages before the final design of the original show, with less fixed weapons and more thrusters instead, the idea being 'it used to have a ton of weapons, but they made it more agile/versatile instead'.
You can assemble one of two different kinds, either the 'early' type or the 'middle' type, which have some differences. You can also choose to build a mixed type and just put as much on it as you want.
The RX-78-2 itself is a more detailed version with more panel lines and a more 'real' look.
There are two options of front chest, one with two closed chest plates or one with one closed chest plate and what seems to be a set of either search lights or cameras on the other side of the chest. The plates can be pulled off and inserted on top of gatling guns ('magnum' gatling guns) that are then placed on the top of the chest instead, so it looks like they've popped up.
For the wrists you can choose the standard kind or one or two wider wrists which have guns mounted inside them. Optionally you can have the wider wrists without guns.
On the back you have the option of one or two beam saber hilts, or one beam saber and a shoulder cannon (two beam saber effect parts included).
Finally you have the choice between two beam rifles, the classic one or an 'early' model which has a camera lens and a bulky battery at the front. You have the option of equipping either one in one hand or one in each hand.
Additionally there is a hyper bazooka (which can be stored on the backside, or one of either rifles) and a shield with a handle and some articulation.
Everything in this kit is nicely detailed and 'The Origin' kits have more parts and are more intricate than earlier HG kits, featuring better color separation and arguably a sturdier build, or at least that's the case for the now five different kits I own from this line.
It has a good range of motion in articulation (compared to older HG kits) and also features a very nice toe bend. The ankle armor is on a central ball joint and is nice and stiff (unlike the one on the HG Leo, for example, these don't pop off easily). There are three sets of hands, one pair of which have a trigger finger.
There are sticker decals, as well as the usual eye/camera stickers and a bit of color correction stickers, optional ones for the joints (looks better without), a large sticker for the bazooka camera (looks bad) and a small yellow one for the V-fin on the crotch (looks okay).
The kit begs to be panel lined to make the details pop.
This kit, however, has stiff competition. There are many RX-78-2 kits in 1/144th scale. I'll list the 'best' options, in my opinion (no particular order):
1. HG RX-78-2 'The Origin': Is the best looking HG with by far the most equipment and options, with the most details of the HG kits. I call this 'the cool kit'.
2. HG RX-78-2 'Revive': This is the 35th anniversary model. It doesn't look special, it doesn't do anything special, but it looks nice and it's 'the cheap option'. Nothing wrong with it, especially if you just want a normal looking grand daddy gundam.
3. Real Grade RX-78-2: An RG that features far more color separation than the rest and better articulation than the Origin/Revive versions, however it's also more expensive, more complicated and very fragile (being the first Real Grade kit). This is 'the real deal'.
4. HG RX-78-2 'Beyond Global': The 40th anniversary kit which has a more classic toned down look, with fewer details, but much better articulation than both of the above kits made with completely different mechanics. This is 'the engineer kit'.
5. HG G40: The other 40th anniversary model kit designed by Ken Okuyama's design company (they helped design the Ferrari Enzo) which looks drastically different, but is based on the original RX-78-2. Probably has even better articulation than the 'BG' version: This is 'the designer kit'. However, it does look more like a toy than an 18 meter tall robot and it's also as expensive as the Real Grade.
In my opinion The Origin kit is the best for most people and the rest are for those who are looking for something more specific.
It looks cool, it has good enough articulation for cool poses, it's not too expensive and it gives you the most choices/options to build it the way you want.