What are they? They can be with either certs or DC. Certs: Spitfire Claymores (Engineer and Infiltrator) Tank mines DC: Solid grey camo (TR) - my all-time favourite purchase with actual money. I love wearing it at night time or when fighting VS. After just doing a nice little 29-killstreak tower stomp during the night of Indar, it reminded me of why I love it so much.
Certs: G2A lockon launcher with dumbfire. Doesn't actually kill air that often, but does a pretty good job at telling them to go away. And it still lets me blast harassers that try to run me over. DC: Membership. Its actually a REALLY good deal.
Decimator/Annihilator and Commissioner with DBC, so that I have them on all characters and any future ones I make.
Membership. You get DC back every month and enough certs to get a new weapon every month (without taking in account XP gains). Then use the monthly DC to buy things which aren't faction specific (so neutral camo and NS weapons).
The warlords bundle. It came with the all newer weapons for each faction and a 6 month xp boost. Few things give that kind of value. You can't even buy a 6 month boost normaly. Combined with the membership and spending my monthly 500 dbc on a boost or 2 for dbl xp events i can easily net +400% xp.
deployment shield for sunderer. i keep recommending it, 50 certs and you get a super tanky spawn point!
Certs: The banshee for the mosquito, that gun has paid for so many other things it's crazy. DBC: The Doku armor & solid red camo, Dawned in a WW1 trench coat in red camo just looks so bad ***. By far the best armor in the game.
Alpha Squad, hands down . Extremely good value since the amount of money you paid was the same as if you just had bought in-game currency, 6 month heroic boost for all new characters, 12 different weapons (4 per empire), some camo/costmetics and a title. Since I bought pretty much everything on sale those initial 4000 station cash (now DBC) lasted a long long time. As for Certs, hmm, gotta be the medic tool. Reliable cert gain and can turn the tide of battle. Though that HE lightning/C4/grenade bandolier sure did a lot of work during ExplosionSide meta, it was absolutely filthy.