It's a matter of personal preference. All stains differ from paint in that they provide color while also allowing the wood's character to show through. A "solid" product is the most opaque and allows texture, but little grain detail, to be seen. Also, opaque products usually last longer because they block out a greater proportion of damaging ultraviolet rays. A "semi-transparent" product allows some grain to be seen. Keep in mind that the more transparent the product, the more its color will be affected by the underlying wood. Variations in wood color, then, will be more obvious with transparent products, as will any natural blemishes such as knots and tannin. Please note, we do not recommend using a semi-transparent stain on wood that previously has been treated with paint or a solid color stain.