Looks like 65C batteries are in stock at Hobby Partz. Limited time only. Jump on them now because you may never see them again.

Kidding aside, I have 8 Gen's Ace packs that I've purchased over the last few years. 6 of the 40C ROAR approved bullet connector type and 2 of the 50C. All great batteries for the money and they are all I ever run anymore. But people come here looking for critiques so here's mine.

The first ones I bought way back when came with Dean's style T-connector adapters. Wish this was still the case. Those stupid connectors they come with now are useless to just about everyone.

They change the part numbers on them then don't submit them for reapproval. So all of the batteries on the HobbyPartz "ROAR Approved" section come with ROAR Approved stickers but only a few of them actually are. You won't be able to run them at an actual ROAR event unless the part numbers match the approval list. The 50C batteries I bought most recently don't match the part number on the approval list.

I don't care about the design on the case, but I've seen better hard case designs on cheap batteries. These are kind of flexible and seem like they could split easily.

There is a wide variance of battery quality. I've rated all my batteries at 10 amp discharges. Some perform very well and others not so well. Surprisingly, my best 40C batteries perform better than the 50C batteries I recently bought both on the discharge rating and on the track.

Only problem I've ever had was the internal solder joint to the tube melted after plugging it in to my speed control backwards (bullet connectors are great, but sooner or later you'll get distracted). I was able to open the case and resolder it. Don't know if my Speedo had reverse polarity protection or not, but I was thankful for the cheap solder joint giving out rather than frying my speedo.

They are only in stock for a few minutes every several months. This goes for just about everything worth buying on the HobbyPartz and related "Nitro Models" web sites. Makes no sense to me how a company can survive when it never has any inventory to sell.

I used online chat for a return once at Hobbypartz (not a battery). I had to wait a while to get someone but had no problem with the RMA after that.