Ah, the age old debate that comes up every so often,
For the record, the ammount of time spent for quals and actual racing is for sure another topic, that is about as good as they get. With that said, I'll put my .02 FWIW.
IFMAR starts and heads up starts each have their own pros and cons. For me IFMAR is my favorite. It's the start system that I have used the longest ('90-'91ish) for the most part, so it's more of what I know type of thing. At the very least it's what I'm most comfortable with. Club race or bigger, doesn't really matter to me. For the racer, IFMAR starts are the way to go. For those wanting to watch, not so much. Heads up on the other hand is the exact opposite.
Does IFMAR starts take longer to run on a given race day? Yup, no real getting around that. The main issue here is that everyone wants their own class to win at, which compounds the time issue. Back in the day when only one or two classes were ran for most club racing that I did, no one complained about the starting system. I doubt that most noticed the extra time, but back then running batts that might last 4:30, any extra time to have that race batt ready was what you were after. I doubt that most cared how they got that extra time. Bottom line here is that, IMHO, there's just too many classes being run on a given race day. Go back a little to just some Stock and Mod classes with a Outlaw Stock or Pro Stock used as a bridge and be done with it. No real need for 50 classes of 2wd buggy just so every one can feel like they are winners.
Does using the IFMAR starts cause more pile ups in the first turn in the main? I don't think so, but it also depends on the class and the drivers in that class. First turn pile ups happen, even in some of the top Pro classes. No one wants to see that, but does happen. If people need some practice at not causing a first turn pile up, they probably need more practice to begin with. That is where the wiley old vets like me should take the time to help those racers. I will try to, but it's not always possible on my end. At the end of the day, "clean" racing is what all racers should be after. That comes from a few different things. Track time and practice, knowing the regular racers that run in the same class as you, taking the time to help the new racer to the class so they learn the right way.
There's nothing worse to me than getting punted in a qual and ruining a perfectly good qual run because some just aren't willing to plan ahead. When it's a new racer to the class, they get the pass and usually some explaination of why they should have done something different afterwards. When done in a tactful or constructive manner, the new racer is willing to learn. I'm totally ok with that. When you get punted by a fellow racer that you race with on a regular basis and should know better, the reaction is a bit harsher. To the point that things have got real close to being toe to toe. Not what anyone wants to se, yet does happen. I've seen that play out more times than not when heads up starts are used. I can understand that racers will have good and bad days at the track, but the fustration levels can get a bit out of hand. I guess that's the competive nature of racing.
When you have a class of racers that are all pretty evenly matched, one bobble, slow marshall, punt, can and often times does mean the difference between making the A main and not. Locally, if I do make the A main, I earned it and it means a little bit more to me. The class of 2wd buggy open/mod is pretty tight for the most part where I run and it's down to the one bobble, slow marshal, or punt that makes the difference of a good run or not. In that case, heads up starts are probably not the best option for that class. But, it's the preferred start system, and I'll go with the flow.