Ambu +2 armor is definitely HIGHLY dependent on job and what you want to do with it. But if I had to pick 5 pieces without knowing jobs/use cases, some of the strongest standouts of all of the Ambuscade armors are:
1) Flamma head
2) Sulevia feet
3) Meghanada hands
4) Sulevia hands
5) Jhakri body
More specific suggestions for highlights by set below; these all hold up as best-in-slot gear or close (like, 2nd-3rd place option for the slot) for certain situations:
Sulevia:
(1) Hands are very solid offense with strong DA/Acc/Atk, plus DT-5% - a staple for any defensive/hybrid sets.
(2) Feet give WSD+7% and are BiS (barring like, amazing Dark Matter augmented gear) for many WS.
Hizamaru: nothing is a must, but...
(1) legs are maybe the highlight of the set with WSD+7% and good STR - they remain a top 2~3 option (though SAM NIN are the main jobs on the set that may care about WSD, and they get AF+3/Relic+3 legs with WSD+10%).
(2) I still use the body when idle/not fighting on all 4 jobs on the set, for the massive regen (+12/tick). Luxury piece, but may never be beaten for that niche purpose.
Inyanga:
(1) Legs are a must for BRDs.
(2) Whole set is very nice idle Meva gear, I make good use of it on WHM BRD.
(3) Whole set also provides pretty strong WHM BRD Macc options (though can be beaten with some stuff like AF+3 pieces, Chironic hose, etc.)
Meghanada:
(1) WSD+7% hands are still BiS for many WS.
(2) The whole set is very strong for all-around ranged use on RNG or COR (including a best in slot preshot piece with Snapshot+10 feet, and a great RNG crit head).
Jhakri:
(1) Refresh+4 body is a must for all jobs on it.
(2) BLU makes very good use of the set for magical nukes (pretty much no worse than a top-3 piece in every slot, only really losing to Relic+3 legs, HQ Amalric hands, very strong Herculean augments).
Flamma:
(1) Head is fantastic, still BiS for many offensive applications
(2) Feet are less amazing (they lose out to some options like WAR AF+3, SAM Kendatsuba+1 or maybe Ryuo+1), but still a very strong option.
Tali'ah: eh, not that amazing (some niche use like strong pet Macc for PUP, one of several good Pet:DT- PUP legs), but...
(1) Body is strong melee acc/TA gear (made a little less impressive for BST PUP when they got on Malignance)
Mummu: somewhat underwhelming, but:
(1) Solid crit gear for certain WS (Blade: Hi, Evisceration, Victory Smite) - particularly hands > feet > body
(2) Rather niche use, but I like hands for ranged crit sets (especially for Empy RNG or COR).
Ayanmo:
(1) In general, excellent melee mage gear for WHM BRD that also comes with some DT- to keep you safe - it's viable to use 5/5 for those jobs. RDM can use it too (and would def want hands for enspells), though RDM does have more options like Malignance set or Carmine +1 legs.
(2) Body can be used effectively in some hybrid builds for RUN (lacking the very hard to obtain Ashera Harness).
Mallquis:
(1) DT-8% body is very nice, great piece especially for those without Shamash Robe
(2) Whole set is pretty good for helixes and low tier nukes (not that low tier nukes are in a very good place in 2020)