Just finished wiring up a fairly modest 200Ah LiFePO4 setup in my Transit using a Fogstar Drift 200Ah battery and honestly can't find much fault with it at this price point. Paid £399 compared to the £700+ you'd drop on a comparable Epoch or the big Victron setups. Built-in BMS, handles 100A charge/discharge, fits neatly under the passenger seat.
Pair of 175W Renogy panels on the roof feeding into a Victron SmartSolar 100/20 MPPT (couldn't quite bring myself to go full budget on the charge controller tbh), and I'm pulling roughly 600-700Wh on a decent day. Running a 12V compressor fridge, phone charging, a couple of USB lamps — it's genuinely enough for 3-4 days without hookup in summer.
The one thing I would flag is the Fogstar app/Bluetooth monitoring is a bit rough around the edges compared to what you get natively in the Victron ecosystem. I ended up adding a cheap Victron BMV-712 shunt just so I could see proper state-of-charge data in the VictronConnect app.
Anyone else mixing budget batteries with better-quality monitoring/charge kit? Curious whether people think it's worth saving the cash on the battery or whether the Victron SmartLithium is actually worth the premium for a van that gets used hard year-round.