I've run Intellects for the last 3 years myself from stick packs to 3800s and 5000s of varying C ratings and my experiences have been..
IP3800 hardcase -- great, no issues, puffed due to heat when running 3.5T in a 5min race (always returned to normal size)
IP4000 stick pack -- great, always performed well in m03r, scx10 and drifter.
IP5000 30C hardcase -- one pack after 12mths went zero voltage AFTER charge cycle but i resurrected it
IP5000 40C hardcase -- puffed slightly after 6mths (approx 50 cycles)
IP5000 50C hardcase -- puffed after less than 4mths (< 20 cycles)
From my experience, it looks like the bigger the capacity and higher the c rating, the more unstable the pack.
What i really want to find out are which packs of around 5000mAh 40C are actually stable, run hard no matter how much is pulled from them or using what electronics/motor etc and dont puff after minimal use.
Recommendations anyone?
The 5000 50C I have 6 months and when the assets are OK and have about 20 discharges,5000 40C discharges over 60 ,5000 30C over the 100.
To consider the use only with 17.5 and 10.5 so I do not know their behavior mod motors.