The HPI ones hold up ok, however, the parts that hold it onto the chassis may break. There is one thing you can do to help, using a larger/longer screw for the supports.
There was a seller on ebay that sold alloy battery tray mounts for a decent price. x-spede. I made my own out of heavy gauge angle iron... then never revisited them to clean them up, so it's pretty hack. I used larger screws on the stock supports underneath the tray.
Was trying LST shocks as I bought mine used and it came with them. But the FLM upper mounts didn't fit right and the lower end wasn't pushed out far enough. Was a bit of a debacle. I replaced them with normal big bores and yellow springs on the rear/white on the front with 45wt oil. So far so good.
I also got the rc4me.us super 5SC transmission with a center diff in it. I had to use my input shaft, and used 750k oil in the center diff, but so far, it's been a great upgrade. I replaced the stock motor/esc as mine was the v1 that was the rebadged mamba monster v1 that wasn't waterproof. I'm running the mamba monster X/2200kv sensored in it now. I only run 4S, but even that was enough to break 3 BP diff pinions before I got the 5SC transmission. So far, no issues and I can actually use a lot more throttle on take off vs ending up on my roof constantly.