What is the best product to use for bugs? The most practical answer is prompt cleaning. Do not delay that weekly car wash for a week or two, when you know better. With that stated, I believe there are a few good options to use for cleaning during this wash process. The Gyeon Bug And Grime has become one of my favorite specialty cleaning options. The benefit of a dedicated product is that it can better navigate the line of being effective at what it does without being too strong to the point of requiring extreme caution in use.
This product, like many milder dedicated products gets a bad label as a non-effective product for bugs and grime, due to there being stronger comparable products. I have even underestimated how effective this product is. So often people have an intense urge to attack minor problems with the strongest recommended cleaner possible. A specialty cleaner that is stronger (than car soap) but safer than a caustic cleaner can help reduce the chances of causing damage to the paint and surrounding areas. Damage to cars in general with strong products is a common problem. I have seen chemical staining from the use of aggressive products that dried on the paint (less margin for error). Also, car paint protection products are more adversely affected by a stronger cleaner.
Spray on the surface directly and allow a slight dwell time. I always allow 1 minute before my car wash process begins.
The instructions state for you to not let the product dry on the surface. If you are looking for clarity with these instructions, I usually leave the product on the surface prior to agitation and removal from 1 to 5 minutes. Heat and sunlight on the surface will shrink that window in half or lead to me waiting for cloud cover from the sun.
As mentioned before, this may be a more forgiving product than a highly alkaline all-purpose cleaner. But I would NOT leave this product on the surface without washing, rinsing, or foaming the area with soapy water for longer than 5 minutes. After allowing the product to dwell on the surface proceed to rinse, foam, and or wash the entire car how you normally would.
I also like to liberally spray this product on horizontal surfaces of cars that have been neglected. I am particularly referring to cars that are frequently outside, have no protection, and have gone a lengthy period without washing. I have found that I can professionally (more safely) remove the grime caked on the top of cars more efficiently by pre-treating the surface with Gyeon Bug And Grime.
The new Gyeon opaque bottles are also an appreciated change. Though I love the design of the older bottles, I have also been concerned in the past about their fragility. These seem more durable. I love the aesthetic of these bottles as well.