They usually have a shorter shaft, so maybe easier than a fairway wood. You'll probably lose distance for the same reason (ignoring loft, which is kinda important). They are more versatile, in my experience.
/ping Gaghalfrunt. He knows clubs better than most.
It's like I heard my name...
Hybrids are not a true 1:1 replacement for fairway woods. They're actually meant to replace long irons, so you're not going to get the same distance from them that you would expect to hit your fairway woods. They're shorter, heavier headed and generally a little more loft than a fairway wood, which accounts for the difference in potential distance. It's possible to build hybrids to the same specs as fairway woods, change the lie angle and weight, etc so that you can create a 15" 43" hybrid with the same general specs as a typical 3-wood which is around 15* and 43" long, but I'm not convinced that's going to help in this case.
If a player is slicing fairway woods and driver and not slicing the irons it's almost always comes down to one of three things: Swinging differently with the woods (i.e. trying to kill them or trying to "lift* the ball into the air from tight lies) which is very common, failing to adapt to the longer shafts of woods which makes them much harder to return to square or relying on the major offset in most game-improvement style irons (like Callaway, Ping, etc) to compensate for the normal outside-to-in swing plane, which is also very common. The good news is that many many hybrids do come with the same major offset found in irons since they're meant to replace irons, so if the swing-path is the problem getting some nice offset hybrids would help players that slice. So it's *possible* that finding a strong-lofted, longer-shafted hybrid like 42" and 16" *could* be a potential replacement for a 3-wood. And it might not help at all because if the problem is swinging differently or not being able to "square-up" a club with a longer shaft then you're trading one club with a problem that makes it harder to hit for another club with the exact same problem. The world is filled with people that can't hit drivers or fairways woods that also can't hit hybrids that are built to fairway wood specs.
I don't think it's a good idea to buy new clubs as an attempt to find a solution to having other clubs that are giving you problems. Fit is important, but nowhere near as important as fundamentals. It's 95% the Indian and 5% the arrow. While it's remotely possible that blindly buying new sticks can result in a dramatic improvement that's pretty rare. The vast majority of the time the problem is in the technique, not the equipment. Instead of buying hybrids hoping for a miracle it will be better to invest that money in a couple of lessons. It's amazing how often seemingly major equipment problems can be solved in a single lesson using the same equipment. Get the swing right first, then and only then worry about getting gear that fits the swing. That's the only thing that works in the long run. And since 99% of golfers don't want to hear that and are looking for the easiest path that doesn't involve effort or practice or lessons and expect to find improvement in an equipment catalog, it's better to have clubs that you can hit solidly shorter distances than clubs you could go farther, but don't because you don't hit them well. So if you're one of those people, by all means, get the hybrids. They might not help, but they sure can't hurt and even if they don't go far enough to be a true replacement for fairway woods, at least they won't be flying so far into the trees.