I'm new to the world of customized audio equipment (and Head-Fi, for that matter), so apologies in advance if these are obvious questions.
I was planning to get a pair of Westone UM2s and outfit them with a pair of customized UM56 tips. Then, I read about the AC2s, which - as far as I can tell from reviews - seem to be somewhat similar to the UM2s, except that the IEM itself is customized (as opposed to adding custom tips to a non-custom IEM). I was hoping someone might be able to shed a little light onto any/all of the following questions:
1) What is the price difference between these two options? On Amazon, the UM2s are selling for $200 and the (silicone) UM56 tips are an extra ~$150 if ordered through Westone, which works out to $350 (not taking into account the price of a fitting session with an audiologist, which would presumably be the same for both pairs). In contrast, the AC2s are selling on Amazon for $400. Is there something I'm leaving out of this equation, or is the difference really only $50? I remember seeing in a thread somewhere that some people have purchased custom tips directly from an audiologist (who not only took the mold but made the tips as well). Have any of you done this instead of ordering through Westone, and if so, how much did you end up paying for the custom tips?
2) What are the advantages/disadvantages to having custom tips vs. the custom IEM? Is fit/isolation going to be better with the latter, or will it be the same? Portability (i.e. being able to use the custom tips with another pair of headphones) wouldn't be an issue because I don't own any other pairs that would be compatible with the UM56s.
3) Is my earlier assumption a fair one, or are there differences in sound quality between the UM2s and the AC2s?
Thanks for any help/advice/answers/recommendations you may be able to provide.