1) It's more private. Bloom filters gives away quite accurate statistical information about what coins you own to whom ever you happen to be connected too. An attacker can easily use this to deanonymize you even if you don't reuse addresses; Tor does not help much against this attack.
There is also an option to download everything, but do only a very basic surface validation (without keeping track of UTXOs).You do not need a full node for that.