Which Pz.35(t) is better, the Academy's version or Tamiya's? Apparently the latter one's a CMK rebox. I need a kit that's easy and quick to build. Any suggestions are welcomed.

I have built Bronco's kit #35065, which is based on an SKP kit but is improved. I read one review of the Tamiya kit that mentioned issues. I found the Bronco kit to be very good, though it is very delicate and detailed. It can be built as pre-war Czech or German. Here is an Armorama review.

https://armorama.kitmaker.net/review/10451

Sorry I didn't read the full text of your request. This is not a quick and easy to build kit.

Another option is the Academy kit with the DEF models upgrade.
http://defmodel.com/

See under conversion sets.

In general, Tamiya kits are usually easier to build with a lower parts count. Here is a link to the Tamiya page for the kit. click on the "manual" link and review the instructions for yourself and decide if it appears easy or not.

https://www.tamiyausa.com/items/plastic-model-series-20/1-35-scale-military-miniature-12000/german-panzerkampfwagen-35(t)-25112

I have the Academy kit (13280). Here is a link for information on the kit. Scroll down to "Instruction Sheets" and you can view and compare the build with the Tamiya version.

https://www.scalemates.com/kits/196683-academy-13280-pz-kpfw-35-t

I personally don't see a big difference between the kits. Parts count is similar. So, you probably won't be wrong with either kit.

I'd say go with the academy, the cmk has fit issues and is not up to Tamiya standards. Unfortunately sometimes Tamiya reboxes inferior kits, but they try to at least improve them with a new sprue or two.
Axademy is their own moulds, easy to build and looks the part. It has link and length tracks if I remember correctly.
Bronco is better with a full interior and individual track links. Neither kit "needs" an upgrade set, but they help.

Academy, hands down. I built a couple of the CMK Pz.35(t) kits back in the late 90s/early 2000s when it was new and "fresh", and as mentioned by others it does have fit issues, rivet-detail is also rather weak in places due to limitations of the original molding (no slidemolds back then), it also lack details in places. I have both the Academy and Bronco kits unbuilt, Bronco is the best detailwise but not for the beginner, Academy is quite good and should be what you looking for, of the three kits available.

As noted already, the Tamiya kit is the CMK kit from 10 or so years ago re-boxed. So your comment regarding Tamiya kits being easier to build really does not apply here. I've built the CMK kit and it is in no way similar or easy to build like a typical Tamiya "home-grown" product.

I liked my Academy kit.

Thank you all for the replies. I guess it's the Academy kit. Only one problem: Academy used to supply really bad decals. Like, so bad that it's as thick as tape and unaffected by Mr.Mark Surfacer. Is Academy's pz.35(t) supplied with those decals?

Anyways I went ahead and bought the Academy befehlswagen. For decals, I will just use Tamiya's. I got some leftovers from other kits. I *might* do a build log for the kit...