I'd like to give you my thoughts on the inner liners of my motoport suit. I love them! The wind/rain liner on my motoport air mesh kevlar pants and jacket make this gear a genuine year-round outfit.
I live in Virginia Beach, VA. We experience all four seasons; July and August are 95-105 F, often times with humidity well above 85%. The liners are, obviously, not installed. If it rains, well, I'm usually in just some undergarments, so I don't care that I get wet. We tend to have beautiful spring and fall weather, though quite often with 20 F + temperature swings. For these seasons, the jacket liner is simply worn (rather than zipped in) for the cooler morning/night temps, and stashed in the pannier during the warmer parts of the day. If it rains, it really is not that difficult just slipping on both the pants and jacket liners (again, they don't need to be zipped in for them to work). The wind/rain liner in the jacket is good down to 55 F with just a T-shirt (for me). I don't wear the pants wind/rain liner until temps are below 45 F, as the regular pants I wear under the kevlar pants seem to do fine (I ride a GS Adv with excellent wind protection for the legs). The thermal liner for the jacket is usually just slipped on over my clothes, even in the winter.
To sum it up, the liner system gives the suit tremendous flexibility. Is it ideal that the outer garments get wet in the rain? No, but the benefit of keeping the wind off me when temps drop far exceed the negative of getting the outer garment wet, especially since "No rain hours" far exceed "rain hours". And for when it isn't raining, I love the air flow the mesh provides on hot and sticky days.
Also, keep in mind that two-thirds of the US population lives within 90 miles of the Atlantic - I would suspect that many of your potential customers have to battle high humidity conditions. For me that means a fused waterproof liner is a no-no.
I really do hope you come up with an outfit that can compete with motoport. Competition is a good thing for consumers. Even if you cannot beat Wayne in price, customer service is important, and, from everything I have read on ADV over the last few years, you seem to do right by folks.
A fool shows his annoyance at once, but a prudent man overlooks an insult.
Give it more gas, if it doesn't solve the problem it will at least end the suspense.