I absolutely love them. My favourite band by FAR. However, they've been utter pants since By The Way in 2002.
I love different eras of them for different reasons, probably erring towards the early days for that absolutely wild, colourful, energetic, dangerous punk funk thing. Uplift, Mothers Milk, BSSM, OHM, Californication and By The Way are stone cold (bush) classics, IMO.
My favourite album is One Hot Minute. It's the most f**** up album they've made and the heaviest. Dave Navarro's guitar playing on it is phenomenal (I don't like Janes, weirdly).
Things that can get in the bin about them these days are numerous;
- the cult of John (his fanboys are tragic)
- the way all of their songs now follow the exact same formula and sound, with Anthony doing the same singing style that started with Stadium Arcadium (my least favourite album).
- the fact they won't take any risks as they once did, even though they're in a position to do that with ease.
- Flea not using a Modulus
Truthfully, I just think my favourite band got old.