After researching, I found several options for the best nail file for acrylic nails. Here are some of the most popular options with their product details, positive and negative aspects, and materials:

1. Glass Nail File Set by Mont Bleu: This set of three nail files is made of tempered glass and comes in a velvet pouch. They work best for natural nails and are available in various color options. The fine glass ensures to seal the keratin layer of the nails and keep them smooth and shining. They are gentle on the nails as well as on the cuticles. However, they might break if too much pressure is applied.

2. Revlon Emeryl Nail File: This glass nail file is available in various colors and is budget-friendly. It gives a smooth finish, can be cleaned easily, and is travel-friendly. However, it might not be convenient for soft nails.

3. Nail Files and Buffers 80/100/180 Grit Professional Nail Files: This set of nail files is made with top quality adhesive tape and emery. They are double-sided, washable, and disposable. They are suitable for both natural and acrylic nails. However, there is no information available on the positive and negative aspects of this product.

4. Tropical Shine 8.5 Inches Nail Files: This set of three nail files is suitable for both natural and acrylic nails. They are made of high-quality materials and are durable. However, there is no information available on the positive and negative aspects of this product.

When choosing a nail file for acrylic nails, it is important to consider the grit level of the file. Coarse files (80-100 grit) are best for acrylic nail extensions, while medium files (180 grit) are best for shaping the natural nail. It is also important to avoid overfiling the nail and to reduce the pressure adequately, especially when working with acrylic nails.