I've used reusable filters in the past, I've used them at work, put them through our labs for testing and I've had a few on my own motors. The points I would say are:
1) Oil on them can cack up MAF and MAP sensors. However if they are oiled carefully and sparingly I've seen plenty of cars do mega miles on them so it's flip of a coin, don't scrimp on cleaning and don't overdo the oiling and all should be ok.
2) K&N have been in the industry for a long time......but their performance in regards to filtration efficiency isn't great. They pass the ISO filtration standards by the tiniest of margins BUT I've seen cars with very pitted exhaust Valves from the superheated particles that reach the cylinders. Very bad for turbos too, bearing wear and oil contamination are a real risk, turbo failure isn't unknown either.
As such I would say if you are going to use a filter of that type, go for either BMC (first choice) or Pipercross. BMC are used by Fiat as OEM in some Alfa's, all recent Abarth's and Maserati's too. While they use a cotton gauze like the K&N, they have multilayer lattice gauze instead of single layer or double layer folded gauze. They have a Claimed 99% efficiency and have Passed OEM testing (our labs testing data was very favourable too), K&N are not fitted by a single manufacturer..... food for thought? Pipercross are multi density foam, which is slightly more restrictive than Cotton but it's filtration is very good indeed.
Pays your money and takes your choice. I like the fact I'm not throwing away filters every service so good for the environment and the comfort of a little extra engine breathing is good.
Why not give it a go?