I am just waiting for my new lenses and a new tripod to arrive! Very exciting! I've ordered the tokina 11-16mm f 1.8 and the Nikkor 35mm f1.8 prime. Now I am looking for filters for them. In the past I have bought filters one at a time so haven't realised how expensive they are! Now I want to buy 6 at once and it really adds up! Usually I use a CPL, a ND8 and a UV for times I don't need the others to gain protection for my lens - I'm very clumsy!!

So a few questions
1- would it be ok to leave a CPL on (except perhaps in low light) to avoid paying for 2 new UV's? Or are there any times its bad to have a CPL on? I know the advantages ( remove glass reflections, increase colour intensity in sky/sea etc) but are there any disadvantages?

2 - At the moment I am looking at Hoya pro1D as I would be worried to put cheap filters on nice glass would reduce sharpness. Any thoughts on decent alternatives that are less pricey or do I just have to bite the bullet and go for these?

3 - I was planning on getting all 3 for both lenses as I hate being in the perfect position for a photo and not having the right equipment! I wonder though if this is really necessary?! I'm sure i will use the 35mm for some landscapes as it is better quality lens than my 18-105 so if I want to go less wide than my Tokina then it will get used. So then I'm wondering if I will need a ND8 for sea shots to blur water or the CPL for mountains to improve colours.... What do you think? Realisitically will the 35mm ever be used for landscapes like that or do you reckon its just too narrow a field of view? (My camera has a 1.5x crop factor)

4- Are there any opportunities to buy a set of all 3 to keep costs down? Seems there was previously a hoya set but no one seems to stock it any more!

5- Lastly (you sigh with relief...) Where do you buy your filters from cheaply?!

Any opinions/advice is much appreciated. Thanks a lot!