nuthatch - I use Instead also and the only days I have to change it frequently are the first few - and I'm changing it a Lot less than I was tampons. I agree with Doc it was weird and tricky the first few times - it could be you don't have it "seated" right? I'm only guessing coz that was my problem the first few times I used it too. The best line I read was: remember the first few times we tried tampons - it took a while to get that right too!
Just as a footnote: because of all the research I did on the Diva Cup - I do "reuse" the Instead cup - only 1 per cycle but I rinse it really well with hot water, reuse it and toss it when my cycle is done.
Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body, but rather to skid in sideways, champagne in one hand, strawberries in the other, body thoroughly used up, totally worn out and screaming: "Yeah Baby! What a Ride!"