There comes that sad time in every value investor's life where he must let go of some of the stocks he likes, because they're just too darn expensive. I'm speaking metaphorically in the case of W.R. Berkley (NYSE:BER); although I liked this stock, I somehow forgot to actually buy it.

It was another good quarter for this small-yet-interesting insurer. Net operating income grew 45% from the year-ago level, and reported net income rose 44%. Other financial numbers were also quite good -- the combined ratio (the ratio of expenses, losses, and reserves to premiums) fell a bit further (lower is better), and premiums written were up more than 4%.

Value aside, there's still a lot to like about this outfit. The company isn't really seeing the sort of irrational pricing/underwriting behavior that can screw things up for everybody, though it did say that growth is requiring greater effort. As such, it's looking for growth between 6% and 12%. The high side of that estimate will likely come from new business units, like an aviation insurance segment.

I also like how this business is structured. Comparisons to Warren Buffett's Berkshire Hathaway (NYSE:BRKb) are too common in the investment world and generally unfair. But there is at least one valid point of symmetry here. Like Berkshire, Berkley operates in a decentralized manner, where the individual operating units are responsible for their own performance and the central office takes care of investing decisions and the reinsurance business.

In this Fool's opinion, insurance remains a sector where good stocks like Berkley, Arch Capital (NASDAQ:ACGL), and Progressive (NYSE:PGR) look a mite expensive, while cheaper stocks like Marsh McLennan (NYSE:MMC) (actually a broker, not an insurance underwriter) or RenaissanceRe (NYSE:RNR) still have some improving to do. That can be frustrating for an investing Fool, but remember to take a lesson from the well-run firms: If the right business isn't at the right price, it's not the right business.

For more Foolish assurances:

Fool contributor Stephen Simpson has no financial interest in any stocks mentioned (that means he's neither long nor short the shares).