I have done a lot of testing with the teleadapter and cheap UV-filter compared to expensive filter vs no filter at all. There is a very slight or no degradation of quality with a expensive UV filter and medium to very much impact on the quality with the cheap UV-filter. I can post some images if you like. So adding 2 uv filters are probbly not a good idea, even if they are of good quality. And leaving the lens adapter on at all times doeasnt work since there is a tunnel effect, vignetting on the wide angle, you have to zoom out, I also thoght of leaving it on for protection but it doesnt really work.