1, no idea i've only run engine few mins so far, doesn't seem any noisier than my previous 'open' filter.
2, Ebay # 111777553513 I used 'make offer' thing at £18 and was accepted (automatically I think) free post too.
They only do blue, I painted mine with some grey Autotek primer I had & a £5 tin of plastikote gloss red. I replaced the nuts bolts with stainless M5x25mm (111690271129). Silicone tube # 111525326610.
The proper genuine K&N filter to fit it is £47, can be had from KN shop freepost
https://www.knfilters.co.uk/search/prod ... od=rc-5052I've put some mesh (leftover from radiator guard) in front of the trumpet too now, stop any big bits of debris. Also thinking about putting a small hole on the 'dirty' side to let out any water that might get in.