I've never actually looked at the Factotum, but based on that one feature ... yes, absolutely. A +3 to all trained skills (from being in-class) is always a nice trick, plus lowering the requirements for PrCs is extra nice. (Only requiring 1 rank for any skill traditionally requiring 4? Absolutely)

Any disincentive to doing this has pretty much been removed, too; since they're no longer penalizing multiclassing (for the campaigns that enforced that rule), it's easier to get the bonus without the ill effects.