Variable Frame Rate Q

I'm working on a project that uses different sources.  Some are 25i and one is 25p.  (My final DVD will be NTSC).

While I use a script that provide good quality 25p to 29.97i conversion, I want to know if it is necessary.

25p content is best converted to NTSC by using 25 to 29.97 pulldown.  Womble is capable of editing and combining 25p with pulldown and 29.97i content.

My question is: is it the RIGHT thing to do?  Variable frame rates (VFR) are acceptable for DVD.  25p content looks better and uses less bitrate if you use pulldown.

It's probably a more philosophical than technical question.  I just feel mixing types is sloppy.

Is there a right or wrong answer?

Not that I assume to know more than you, cause Im sure I dont, but how is the source 25i? I thought all PAL content was progressive 25p? Or is this one of the annomilies thats a freak of nature.

As for mixing, I guess its a judgement call, I think using the best sources possible is best, but I realize this isnt always the scenario. What kind of interlaced pattern is the 25i using, just curious?

Just like NTSC Video is true 29.97i, PAL has an equivalent.  It consists of 50 unique fields interlaced together.

My current favorite conversion script for this type of content:

mpeg2source("PAL.d2v")
loadCPlugin("yadif.dll")

yadif(mode=1) # Smart bob mode doubles framerate (using interpolation and masking) (50fps)
Spline36Resize(720,480)

#extrapolate new frames (true in-between frames, NOT blended) (59.94fps)
super = MSuper(pel=2)
backward_vec = MAnalyse(super, isb = true)
forward_vec = MAnalyse(super, isb = false)
MFlowFps(super, backward_vec, forward_vec, num=60000, den=1001, ml=100)

#reinterlace (29.97fps)
AssumeTFF()
SeparateFields()
SelectEvery(4,0,3)
Weave()
converttoyuy2(interlaced=true)

Ok, no opinions on the matter.  Interesting.