if all of your EPs are 1.25 then you would be better off getting a 1.25 barlow. no sense in getting a 2" barlow if you dont have EPs to go in it.
2" EPs are good for the extra FOV they give you. I have got only one 2" EP (a 30mm GSO SV) and wouldnt dream of barlowing it as it would defeat the purpose of me getting it.
this said, if you plan on getting a collection of 2 inch EPs then go for it.
