my .02 and observations having stayed on the West End in 2008 and Utila last spring:
For somewhere I was going to temporarily live, I'd pick Roatan. The West End has a lot of nightlife but is still quiet mid-week. Half Moon Bay beach was nicer than anything I saw on Utila - that wasn't private property. My group likes to party a little bit after diving, we found that on the West End. Nice mixture of locals, dive people and tourists. Sundowners right on the water is a diver's hangout - good basic food also.
The best beach areas on Utila are on private property afaik. Most of the dive training/resorts are in town and there's tiny beach areas adjacent to some of them. Look at
Utila Lodge's website, they have pictures of town. btw, the diver with the whaleshark is a certified researcher tagging it, you don't get to do that...snorkel only.
Utila is really quite small. Most of the island is uninhabited. The port is some small stores, maybe a dozen restaurants, some bars and dive outfits. No hospital, the clinic also houses the chamber. Many people ride ATV's or walk - there's a few cars/trucks.
Roatan has a small hospital and chamber at AKR. They also have some larger food markets - one in Coxen Hole is the size of a small U.S. food store, butcher, produce etc. and smaller options in the West End and elsewhere - Woody's is like a big 7/11. Lot's of dirt cheap to very expensive dining options also. From $5 burgers at Sundowners to a Thai place nearby that was pretty pricey. Argentinean Grille had good $20 steaks and we also had a $5 lunch at a pasta place a block from where my friends were staying - good for lunch between dives.
One night in the West End we needed a doctor - found one 5mins. away. Later that night my friend needed a hospital - we were able to call an ambulance for transport. I don't think that would be possible on Utila. Something to consider when doing a lot of diving in a smaller country.
A friend just did her DM/Instructor with
Coconut Tree Divers - we dove with them in 2008 - they're good people. They have a dorm for people taking classes with them - it's $5/nt. The owner, Gay, told us she took one of their larger cabins and put 6 bunks in it. My friends blog:
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Just for the amount of other activities I'd pick Roatan. There's even a couple of American food chains in French Harbor.
Access to the mainland is about the same. There's a twice daily ferry from either location to La Ceiba. Both seemed to be a mix of locals, backpackers (Utila Princess) and tourists. Each takes about the same time and costs $21 or $31 each way. It seemed like many locals bought stuff on the mainland and brought it back to Utila - didn't notice that as much going back to Roatan. Of course that's based on 2 Saturday rides.
Flights to Roatan direct are a little more expensive but the puddle jumper thing through SAP sounded a little wearying. Depending on scheduling it often also means an overnight there or in La Ceiba. We even flew to Roatan and then took the ferries on to Utila last year. For us it was the difference between a $1200 red-eye - 1PM arrival or $700 same day with a 5PM arrival on Utila.