Are Zippy Lipos safe with a Castle MMM Speedy?

[RC-Monster Mike]

As a general rule, you get what you pay for. There are of course exceptions to every rule. Hobby City freely admits that their Zippy and Flightmax packs are lower end packs - expect less cycles and lower charge rates vs. the higher cost packs(there is a quote on the boards here somewhere). They are a good "value", but the expectation that they are the same quality and performance as a higher end pack costing 2x as much is unrealistic. This doesn't mean they won't work or are "bad", but we have to be realistic. Likewise, your idea of "pushing your erevo and emaxx brushless very hard" may differ from someone else's idea of the same, which is part of the danger of the internet - no 2 people operate in exactly the same conditions, so a lot of info requires speculation.
I also agree on the newer Maxamps packs - very good packs - pricey perhaps, but far better than their previous generation. :)