First, congrats A4 on kicking the habit!!!
Next petiebear, I too am in search of how to get all the imperfections out. I started out with a PC XP and purchased the following Menzerna products.
Power Gloss, SIP & Super Finish
I have the CCS 5.5" pads and tried combinations from Yellow, Orange, White and Black. I just never got out everything no many how times I did it. I looked at the patterns of the scratches and it wouldn't indicate they were coming from the pad.
So I ordered a Flex 3403 and got a mercedes black door from a paint shop and worked on it this weekend. I have some pix posted in a separate thread, looking for help with a 3403.
I know you're using the 3401 and I'm exchanging my XP for one this week. With the 3403, my best results were starting out with SIP & an orange pad or in some sections Power gloss with a purple wool 6.5". This left quite a bit of swirling so I would follow it up with SIP & an Orange.
One of the best results I came up with so far was ending with the Menzerna Nano Finish using a black pad on the 3403. In some cases I used the PC XP with a white and the Nano finish but I spent about 4 to 5 minutes on the section going extremely slow about 1" per sec at speed 6 and then I dropped the speed down to a 3 for the final minute and no pressure just let the machine continue to break down the polish.
I'm starting to get the suspicion that you just aren't going to get every scratch, swirl out. Mainly the ones that you can't see in a pix.
The other thing, in going through all my testing I noticed that sometimes, the towels I were using to clean the polish off sometimes would leave some light scratching barely visible.
A couple of times when i ran the back of my fingers which were clean across the metal to get a feel for temp as well as smoothness, they actually left some mico scratches. (Still can't believe they did.)
Other things I took away from my testing. With the PC XP it seemed that it would take forever to break down the polish and really never to the point of my 3403 Rotary. The rotary at 1500 to 1800 RPM would seem to break down most of my Menzerna's in about a minute or so. With that said, I don't know with the 3401 but the point is I think I actually ran my Rotary too long in some instances and that kept contributing some of the swirls I was seeing after some of my sessions.
Hopefully my new 3401 will be here tomorrow. I plan on attacking the panel with the Nano Finish and either a white or black(gray) pad at varying speeds and lengths of time. I'll my results and keep an eye on what you find out as well.
Also, I think patience is key, before just jumping in too far, check with a body shop with scrap piece from a Vette, Mercedes etc. I found a black MB door and Red Mustang fender. My steps got extremely good results on the Red and more reason I just have my doubts on something that's driven, whether you can expect to get out every imperfections. I'm not going to quite trying though.
Good Luck
P.S. I meant to say somewhere you may want to try the Super Insensive with an Orange and the finish up with the Nano Finish and a white or black pad.