I did my Rescue with UDC in 2008 (I think?), I did my Divemaster with Deep Blue Divers in 2011, and I did my IDC with Coral View in December of 2011.
I'd consider that a rather broad experience on Utila as most divers pick a shop and stay at it.
Every shop "feels" different. It either fits your style, or it doesn't.
But in the end, the major difference is the instructor who you will learn from. One thing I can tell you about any instructor on Utila is that they will follow the PADI system to the letter. So in essence, what you learn will be exactly the same. When the IE came around, "the other guys" did their skills exactly the same as I was taught. What changes is the personality of your instructor. No one on any internet forum can ever tell you which personality best fits you. Only you can decide this. Upon arriving on Utila you could effectively interview each Course Director within a day or two, assuming pre-arranged appointments. Perhaps I'm mistaken, but I believe there are no less than 5 CD's living here fulltime and at least one more that travels here for IDC's. I also think there will be at least one more by the time you plan to arrive whom is already living here fulltime. Plus take the time to walk the shops, see how they operate, "feel" the vibe. On that same token, I'd be hesitant to pay any shop a deposit on classes before getting to Utila - especially non-refundable deposits. What happens if you arrive and don't mesh with your instructor?
HTH