Well, the newer GL's are a little more similar sonically to the ML series than the old GL series. This is actually a pretty big improvement. More headroom, cleaner preamps, more musical sounding EQ. Still not the greatest sounding thing on the market, but certainly nicer than the older GL series and an excellent desk when comparing feature to price to performance to sonic quality to durability.
Not really my first choice for recording though. However, you aren't going to get much better for the money that also offers the feature set that the GL's do.