Linkwitz transform - free bass or just plain evil?

hi

Does using a Linkwitz transform have any nasty sonic effects (apart from power/efficiency/spl issues)? thought about using it with a big sealed box with a low Q...

I used the calculator here:

http://sound.westhost.com/project71.htm

and put in these numbers:

Fs 25Hz
Qts 0.2
Vas 276 litres
Vb 120 litres

and got a low system resonance and a low end that begins rolling off above 100Hz - seems like an ideal candidate for correction, but I'm just wondering about any side-effects.

thanks!