Been using Team Orion 2S Carbon Pro Ultra 110C Shorty 7.4v 5000 mAh lipos (4mm plugs) for almost 5 years now and never had even one single issue with them. Accurate figures, good punch and keeps offering high performance throughout while in use, holds charge very very well, when stored even after 1+ year at some point: stayed perfectly balanced, no perceptible fading due to age, still very low IR(or low enough not to cause any temp issues), performs as good as new to this day.
Conclusion: light, powerful and durable, couldn't be happier with this product.

Only downside: quite often on backorder like many other Orion products.


Recently purchased SMC True Spec Extreme Graphene V2 7.4V 5200 mAh 120C Shorty 5mm. Too early to call but my very first thoughts is that except for the tube size and design, I find them to be very similar to the Orion above and in performance so far...time will tell.
Pro: seems like pretty good value for what it has to offer.