Well, are you using first gear to slow you down? If you are, that is referred to as engine breaking and is usually considered not healthy for your car. If you are trying to downshift for acceleration, it takes lot's of practice to learn how to do it correctly. We actually had a previous thread about this. Do a search on double-clutching and I gave an explanation of how and why to do this. To summarize though, downshifting into first causes a lot of wear and tear on the vehicle. I don't kniw where you are getting the whining noise from.
Like I've said in the past, unless you have a rear wheel drive vehicle and downshift on snow/ice to keep the car straight, using transmission to slow down by downshifting makes zero sense. That's what breaks are for. Cheaper to replace brakes for 100 bucks than to replace tranny/clutch for $1500. I can see maybe going down to 3 rd, but that's about it.
I must disagree with you gentleman, after all these are "sports cars".I mean you have to use common sense , as for myself from driving the car for a while I know where my rpm are going to be at when I down shift. Don't hammer it but taking the car up to 3500 to 4,000 rpm on a down shift isn't going to hurt anything. I mean it wouldn't be any fun when I'm driving aggressively, that I couldn't brake hard and down shift into the corners.Occasionally at stop lights very gingerly into first gear as well.Adios Amigos