I think it really depends on the spline, I personally prefer the extrude NURBS as it makes neater polys. You can use whatever suites you and if you have trouble with some edges try making the extrude/loft editable and arrange it via the modeling tools. R10 has a great tool for closing holes in a poly (I don’t think R9.6 has it).
Hope it helps and you can keep on, ohh and by the way, on your other post (the one on the lights), perhaps you could get a little bit into expresso, it’s really not that difficult but mograph is definitely worth it (not just in this case it’s overall a great tool). Mylenium (here on the creative cow) has some great tutorials on MoGraph and the last one (the sound effector one #11) has some expresso on it that can help you agetting a general idea. You can also try http://www.c4dcafe.com, great tutorials in there.
Regards
Alejandro