I avoid using LGPL (actually, I avoid GNU licenses altogether).
If you use Qt you can buy a commercial license or use the LGPL license (see here). Since I'm not even sure there is a viable Qt 5 build which links statically that seems to be almost a restrictionless license.
The main problem, specially when considering commercial games, is that LGPL also allows the user to use a modified version of the library (free to use). By using the LGPL licensed resource, you accepted this. It opens a wide plain of possibilities for problems. Unofficial, hacked, versions of the library would float around the Internet. Still, if your game is single player, there'll be nothing to worry about. But by the time you decide to make it multiplayer and hacking start to affect the experience of other players, you won't be able to touch cheaters. If they stay inside the library interface, there isn't much you can do. You'll see that the cheaters will probably fall into a penumbra between your TOS and the restrictions imposed by the LGPL, that states clearly:
Now, whether your work is an application or a combined work differs only if you link it statically. So, no static linking or you'll also allow, beyond the usage of modified versions of the library (despite of its purpose), reverse engineering and debugging. In other words, if you use a shared link you've got problems, but if you link statically, they're really worse.
3. Object Code Incorporating Material from Library Header Files.
The object code form of an Application may incorporate material from a header file that is part of the Library. You may convey such object code under terms [...] you do both of the following:
a) Give prominent notice with each copy of the object code that the Library is used in it and that the Library and its use are covered by this License.
b) Accompany the object code with a copy of the GNU GPL and this license document.
4. Combined Works.
You may convey a Combined Work under terms of your choice that, taken together, effectively do not restrict modification of the portions of the Library contained in the Combined Work and reverse engineering for debugging such modifications [...]
I guess this was one of the main reasons SDL dropped LGPL in favor of zlib. It surely was the main reason I avoided SDL in favor of SFML and Allegro for so long...
Why would the Qt Project provide a commercial license? If LGPL was really a good license, there'd be no reason for them to provide a better one.
Just to make sure I'm not confusing anyone, this wouldn't apply to applications that were created using the QtCreator IDE, given that you only used the IDE. It only affects things that needs libraries or actual code from the Qt Project.