Below is my view on the best 400 scale moulds for a selection of Boeing types based on buying a lot of 400 scale models and looking at them in detail across many years. You may not agree but if you don't you should at least mount a sensible argument about why you don't!
This is part of a series covering the Best Moulds in 400 Scale. See the mainpage for a breakdown of what I'm trying to achieve and why, and also to access other pages in the series:
NOTE: Just because a mould isn't the best it doesn't mean it isn't good and that you shouldn't buy it. I buy a wide range of good moulds for many of these types myself. In the end your collecting is up to you. Use the resources linked to below to get a better understanding of what is available.

-100/200/300
The original 747 has a long list of moulds that have been made for it but there have been no new moulds made since the dreadful Phoenix effort in 2008. Sadly the awful Phoenix version is about the only mould still regularly used, although only a few years ago Aeroclassics did acquire a set of blanks for one of the BigBird clones and they turned out very nicely. There is a stigma attached to Dragon Wings models, however their ancient 747-100/200 is still a nice effort if you can forgive the undercarriage and often poor cockpit printing. Most of the other moulds are decent enough and older Aeroclassics / BigBird 747s remain incredibly highly sought after. The best mould overall however is the seamless Aviation400 / Witty Wings version used between 2007 and 2014 for only about 40 releases.

NG Models have just announced that new 747 Classics will be coming in mid-2023 so I eagerly await those.
SUPPORTING MATERIAL
ACTIVE MOULDS
* The history of the Big Bird Your Craftsman mould is complicated and the current version used by BB Mk3, JC Wings and sometimes Aeroclassics is not actually the original Big Bird mould but seemingly a clone.

​BEST MOULD

​HIGHLY RECOMMENDED
* This mould was also used by the old Aviation400 and Inflight400

​The mould is inactive

SP
The arrival of the NG Models 747SP sparked hope for an avalanche of great 747s. That hasn't really happened and usage of the new SP has been poor, however there is no doubting it is easily much superior to both the Gemini Jets / JC Wings and the Herpa versions.
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* possibly inactive

​BEST MOULD

-400
Like the series 100/200 the series 400 has a very complicated mould history with large numbers of moulds from often mystery meat style brands. Most of these can be safely ignored as they are rare or have gone to paint bubble or zinc rot hell. In general the 400 series moulds share the same characteristics as the 100/200s. This means the 'new' Phoenix mould is godawful, the Dragon mould has obsolete undercarriage but is otherwise good, the old Gemini / JC Wings version perfectly respectable, the Big Bird / Aeroclassics is very nice, highly sought after but rather old fashioned and the Apollo / Witty Wings versions are variants of the Big Bird. The big news in recent years has been the advent of the new JC Wings 747-400 from 2020. This mould could do with longer undercarriage and better cockpit printing but is otherwise excellent and available in flaps down configuration too. 
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​BEST MOULD

HIGHLY RECOMMENDED
* Only the 2020 seamless mould
Special callout here for the new interactive 747-400 freighter version, which is also excellent. 

-8I / 8F
NG Models are just about to enter the 747-8 fold but until now the type has been the battleground of JC Wings / Gemini Jets and Phoenix. Of the two the JC Wings / Gemini version is easily the best, as the Phoenix has a sloppy wing join and the usual rubbish vertical stabiliser join too. The Phoenix is however light years better than their 747-400 mould! The only fly in the ointment is the hump form of the JC Wings 747-8F variant, but I'd probably still take it over the Phoenix anyway and it of course also has an interactive version, which I like a lot.
I'll exclude the NG Models version for now since it hasn't been officially released yet however the mould appears to be the best of the three from the samples as long as NG fixes the print issues raised.
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ACTIVE MOULDS

​BEST MOULD

Dreamlifter
The JC Wings Dreamlifter is the only game in town and although it isn't interactive it is based on the very good new JC Wings 2020 747-400 and has a flaps down variant too.
BEST MOULD