Beseler 810V-XL Enlarger Questions

Hi, I was fortunate enough to pick up a Beseler 810V-XL enlarger in very good working condition with the Aristo cold light head and the Beseler HD-APO 240 F9 lens.

I have a couple questions that I am hopeful current or previous owners can help me with.

1 - It appears there is two ways to load an 8x10 negative. Method 1 is the negative carrier which has a clip on the far end of the carrier (towards the back of the enlarger). My question/concern is will this open frame carrier with only one clip really hold the negative flat? Method 2 is a sandwich between a white diffuser and a piece of glass. This method will clearly hold the negative flat but seems to be hit or miss on proper alignment. Any comments/thoughts about this based on experience?

2 - When I load a negative and project it on the easel, I get vignetting/clipping on smaller prints around the edges. Is this a function of the 240 F9 lens or is something else going on? I was told the HD-APO Lens could do 1x to 3x enlargements from the 8x10 negative.

3 - Any comments or thoughts about the Aristo Cold Light head and its use on this system?

Thanks!