My daughter had a minimially invasive (laporoscopic) gallbladder surgery go seriously wrong precisely because the surgeon couldn't see what he was doing and mistakenly cut the common bile duct instead of the artery for which he was aiming.
Minimally invasive surgeries are great when they go right, which is most of the time, but real bad when they go wrong. Dr. Jim Alexander at the University of Florida, a very senior heart surgeon and personal friend, advised me against it because, if something goes wrong, you will then need to be totally opened up at the worst time to do it. (By the way, he was the one who helped me find the peds surgeon who straightened out the mess my daughter was left in).
Obviously, the minimally invasive approach is well worth considering for cosmetic reasons, especially for ladies (us guys usually get a lot more mileage out of our 'badges of honor'). And, although it generally does not decrease the operative time, and my increase it, it generally does diminish the recovery time and discomfort somewhat.
However, don't think there's no trade-off involved. There does seem to be an increased risk of mistakes being made, as well as complications for dealing with anything that goes wrong.
If, after deliberation, your mother does decide to get the big scar, all is not lost. After only 3 months, my scars have greatly diminished and, just recently, I recieved an injection from a skin doctor (cortisone or steroid, I'm not sure which) that has pretty much reduced the only part on the lower end that was elevated and had not returned to a flush level with the rest of my chest. Also, there are various products on the market to improve scar healing and reduction of appearance, such as Mederma ointment or special silicon gel packs.
Hope this helps.