I've received pretty good service on board KLM both short and longhaul. Also the service centre has been very responsive when I've needed help. However their "new" business class is very dated and is a world away from today's market leaders. There is also no way I fancy a 12 hour trip on a near 30 year old 747 Combi, when there are so many better alternatives out there.
As for AF- well there is no way in the world I would step onboard one of their aircraft. (personal choice- you might like them)
One wonders if KLM were not saddled with AF, they might actually have still been up there with the big boys.