If you're looking at a boat in the 18' to 25' range (6.1m - 7.62m) then it's pretty likely that it will have a 5.0 liter engine as its standard power plant. Volvo Penta's 270-hp version of this size engine is very popular, for not only its size, but also its ability to accommodate either the single prop SX drive or the Duoprop drive.
If you are thinking about upgrading from the standard 4.3 L engine, you should know that Volvo Penta has been able to get 20% more horsepower out of the 5.0 L engine compared to the 4.3, even though its displacement is only 16% more.
This engine produced a top speed of 47.8 mph in a test of the Glastron DX 215 BR. Best cruise was at 3500 rpm where the boat went 29.8 mph and got 3.08 miles per gallon.
In a Regal 3060 Commodore we saw a nearly identical top speed of 47.7 mph with twin 5.0 L engines, and a best cruise of 25.8 at 3000 rpm, getting 1.73 statute miles per gallon.
Power steering and trim are standard and they are available with SX or DP drives.